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test/708419: 5/2 Write each improper fraction as a mixed number
1 solutions

Answer 436104 by solver91311(17077) on 2013-01-30 17:29:44 (Show Source):

You can put this solution on YOUR website!

Use integer division -- the kind where your answer is a quotient and a remainder. Divide the numerator by the denominator. The quotient is the whole number part of the mixed number. The remainder is the numerator of the fraction part of the mixed number, and the divisor is the denominator.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

The Out Campaign: Scarlet Letter of Atheism

Linear-equations/708411: 5y+7x=10=0
Please help :c
1 solutions

Answer 436100 by solver91311(17077) on 2013-01-30 16:59:17 (Show Source):

You can put this solution on YOUR website!

What help do you want?

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Equations/708410: What is 8-(4-n)=18 if n doesn't equal anything?
1 solutions

Answer 436099 by solver91311(17077) on 2013-01-30 16:58:33 (Show Source):

You can put this solution on YOUR website!

What do you mean "n doesn't equal anything"? Of course it equals something. It equals that value that makes your mathematical statement true. Add -8 to both sides, then add 4 to both sides.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Average/708404: If you have a 64% average in math, and you get a 40% on the exam. And the exam is worth 20% will you fail the course?

1 solutions

Answer 436098 by solver91311(17077) on 2013-01-30 16:56:38 (Show Source):

You can put this solution on YOUR website!

Your score will be 80% of 64% plus 20% of 40%. Do the arithmetic. Whether that is a failing grade or not depends on your school policy or your instructor's interpretation. If it were my class where 75% is passing, I would have just told you not to bother taking the last exam because you were going to fail anyway.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Inequalities/708402: Write the slope intercept form of the equation of each line:
5y+7x+10=0

1 solutions

Answer 436097 by solver91311(17077) on 2013-01-30 16:47:27 (Show Source):

You can put this solution on YOUR website!

Solve for

in terms of

Add

to both sides. Multiply both sides by

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

test/708401: A lot has an area of 3,000 sq ft. Its length is 35 ft greater than its width. What are the dimensions of the lot?
1 solutions

Answer 436096 by solver91311(17077) on 2013-01-30 16:44:52 (Show Source):

You can put this solution on YOUR website!

Since area is length times width:

Put the quadratic in standard form and solve for

, then calculate

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

logarithm/708399: How is log 7x +log 7y -log7z as a single logarithm?
1 solutions

Answer 436095 by solver91311(17077) on 2013-01-30 16:41:58 (Show Source):

You can put this solution on YOUR website!

The sum of the logs is the log of the product and the difference of the logs is the log of the quotient:

Note: You still need to simplify the log argument.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

test/708398: Solve the following:
(x - 12) (x + 3) = 0

1 solutions

Answer 436094 by solver91311(17077) on 2013-01-30 16:37:15 (Show Source):

You can put this solution on YOUR website!

Use the zero product rule.

So either

.

Solve the two equations for the two values of

in the solution set.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Sequences-and-series/708394: five times a number, decreased by 58, is negative 23. find the number?
58 minus negative 23= 81. then 81 divide by 5=16.2
1 solutions

Answer 436092 by solver91311(17077) on 2013-01-30 16:33:41 (Show Source):

You can put this solution on YOUR website!

Add 58 to both sides, then divide by 5.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Rational-functions/708367: Please help me to understand the process of answering this question. I would really like to master this concept! :) Thank you in advance.
Let f(x) = x + 5 and g(x) = x^2. Find (g ° f) (4)
1 solutions

Answer 436090 by solver91311(17077) on 2013-01-30 16:31:00 (Show Source):

You can put this solution on YOUR website!

If

is a function defined by

, then if you are asked to evaluate

at some number, say, 2, which is to say evaluate

, you simply have to substitute 2 for every instance of

in the definition of

. That is:

Likewise,

and

Doing a composite,

is nothing more than evaluating the first function at the value of the second function, that is

For your problem, you want

composite

, which is just

, or

Whether or not your instructor expects you to expand the squared binomial is a matter between s/he and you. In any case, you still need to evaluate

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Quadratic_Equations/708365: I am lost. How do I solve this? 3a / 4a-20 + 9a / 6a-30
1 solutions

Answer 436088 by solver91311(17077) on 2013-01-30 15:46:55 (Show Source):

You can put this solution on YOUR website!

You can't "solve" it. You cannot solve something that doesn't contain a relationship operator, like equals, greater than, or less than. You can simplify it, but you have to repost your problem using parentheses liberally so that it is completely unambiguous as to which terms are in your numerators and which are in your denominators.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Probability-and-statistics/708312: Please show the work. Thank you
Problem 60
Refer to the Real Estate data, which report information on homes sold in the Phoenix, Arizona area last year.
a. Create a probability distribution for the number of bedrooms. Compute the mean and the standard deviation of this distribution.
b. Create a probability distribution for the number of bathrooms. Compute the mean and the standard deviation of this distribution.
Data:

Price Bedrooms Size Pool Distance Township Garage Baths
263.1    4     2300  1      17       5        1     2
182.4    4     2100  0      19       4        0     2
242.1    3     2300  0      12       3        0     2
213.6    2     2200  0      16       2        0     2.5
139.9    2     2100  0      28       1        0     1.5
245.4    2     2100  1      12       1        1     2
327.2    6     2500  0      15       3        1     2
271.8    2     2100  0       9       2        1     2.5
221.1    3     2300  1      18       1        0     1.5
266.6    4     2400  0      13       4        1     2
292.4    4     2100  0      14       3        1     2
209.0    2     1700  0       8       4        1     1.5
270.8    6     2500  0       7       4        1     2
246.1    4     2100  0      18       3        1     2
194.4    2     2300  0      11       3        0     2
281.3    3     2100  0      16       2        1     2
172.7    4     2200  1      16       3        0     2 
207.5    5     2300  1      21       4        0     2.5
198.9    3     2200  1      10       4        1     2
209.3    6     1900  1      15       4        1     2
252.3    4     2600  0       8       4        1     2
192.9    4     1900  1      14       2        1     2.5
209.3    5     2100  0      20       5        0     1.5
345.3    8     2600  0       9       4        1     2
326.3    6     2100  0      11       5        1     3
173.1    2     2200  1      21       5        1     1.5
187.0    2     1900  0      26       4        0     2
257.2    2     2100  0       9       4        1     2
233.0    3     2200  0      14       3        1     1.5
180.4    2     2000  0      11       5        0     2
234.0    2     1700  0      19       3        1     2
207.1    2     2000  0      11       5        1     2
247.7    5     2400  0      16       2        1     2  
166.2    3     2000  1      16       2        1     2
177.1    2     1900  0      10       5        1     2
182.7    4     2000  1      14       4        0     2.5
216.0    4     2300  0      19       2        0     2
312.1    6     2600  0       7       5        1     2.5
199.8    3     2100  0      19       3        1     2
273.2    5     2200  0      16       2        1     3
206.0    3     2100  1       9       3        0     1.5
232.2    3     1900  1      16       1        1     1.5
198.3    4     2100  1      19       1        1     1.5
205.1    3     2000  1      20       4        0     2
175.6    4     2300  1      24       4        1     2
307.8    3     2400  1      21       2        1     3
269.2    5     2200  0       8       5        1     3
224.8    3     2200  0      17       1        1     2.5
171.6    3     2000  1      16       4        0     2
216.8    3     2200  0      15       1        1     2
192.6    6     2200  1      14       1        0     2
236.4    5     2200  0      20       3        1     2
172.4    3     2200  0      23       3        0     2
251.4    3     1900  0      12       2        1     2
246.0    6     2300  0       7       3        1     3
147.4    6     1700  1      12       1        0     2
176.0    4     2200  0      15       1        1     2
228.4    3     2300  0      17       5        1     1.5
166.5    3     1600  1      19       3        0     2.5
189.4    4     2200  0      24       1        1     2
312.1    7     2400  0      13       3        1     3
289.8    6     2000  0      21       3        1     3
269.9    5     2200  1      11       4        1     2.5
154.3    2     2000  0      13       2        0     2
222.1    2     2100  0       9       5        1     2
209.7    5     2200  1      13       2        1     2
190.9    3     2200  1      18       3        1     2
254.3    4     2500  1      15       3        1     2
207.5    3     2100  1      10       2        0     2
209.7    4     2200  1      19       2        1     2
294.0    2     2100  0      13       2        1     2.5
176.3    2     2000  1      17       3        0     2
294.3    7     2400  0       8       4        1     2
224.0    3     1900  1       6       1        1     2
125.0    2     1900  0      18       4        0     1.5
236.8    4     2600  1      17       5        1     2
164.1    4     2300  0      19       4        0     2
217.8    3     2500  0      12       3        0     2
192.2    2     2400  0      16       2        0     2.5
125.9    2     2400  0      28       1        0     1.5
220.9    2     2300  1      12       1        1     2
294.5    6     2700  0      15       3        1     2
244.6    2     2300  0       9       2        1     2.5
199.0    3     2500  1      18       1        0     1.5
240.0    4     2600  0      13       4        1     2
263.2    4     2300  0      14       3        1     2
188.1    2     1900  0       8       4        1     1.5
243.7    6     2700  0       7       4        1     2
221.5    4     2300  0      18       3        1     2
175.0    2     2500  0      11       3        0     2
253.2    3     2300  0      16       2        1     2   
155.4    4     2400  1      16       3        0     2
186.7    5     2500  1      21       4        0     2.5   
179.0    3     2400  1      10       4        1     2
188.3    6     2100  1      15       4        1     2
227.1    4     2900  0       8       4        1     2
173.6    4     2100  1      14       2        1     2.5
188.3    5     2300  0      20       5        0     1.5
310.8    8     2900  0       9       4        1     2
293.7    6     2400  0      11       5        1     3
179.0    3     2400  0       8       4        1     2
188.3    6     2100  1      14       2        1     2.5
227.1    4     2900  0      20       5        0     1.5
173.6    4     2100  0       9       4        1     2
188.3    5     2300  0      11       5        1     3

1 solutions

Answer 436087 by solver91311(17077) on 2013-01-30 15:35:49 (Show Source):

You can put this solution on YOUR website!

Use

where

is the

th data element of

data elements

to find the mean. Just add up all of the numbers in the column under Bedrooms (or Bathrooms for part (b)), and then divide by the number of pieces of data. I used

because you are dealing with a sample (mnay more than 105 homes were sold in the Phoeniz, AZ area in a year.). If you are considering this set of data to represent the entire population, use

instead of

.

and then you have to decide whether you are calculating the standard deviation for this sample as if it were the entire population or you are using this sample to to estimate the standard deviation of the entire population.

In the first case calculate the population standard deviation using

or in the second case calculate the sample standard deviation using:

You can do your own arithmetic. Have fun.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Travel_Word_Problems/708281: A projectile is launched from the ground with an initial velocity of V0 feet per second. Neglecting air resistance, its height in feet per seconds after launch is given by s = -16t^2 +V0t. Find the time(s) that the projectile will
(a) reach a height of 240ft and
(b) return to the ground when V0= 128 feet per second.
1 solutions

Answer 436042 by solver91311(17077) on 2013-01-30 12:13:10 (Show Source):

You can put this solution on YOUR website!

(a) Set the function equal to 240.

Substitute your given value of

and then solve the quadratic. The equation will have two zeros, one representing the time the projectile reaches 240 feet on the way up, and the other representing the time the projectile passes 240 feet again on the way back down.

(b) Same as part (a) except you set the function equal to the height of the ground, i.e. zero. Your two zeros will be zero and some positive number. The zero root represents the instant of launch, and the other is the time of return to ground.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Numbers_Word_Problems/708283: the sum of one-third of a number, one- fourth of the number, and one-eighth of a number is thirty four find the number
1 solutions

Answer 436039 by solver91311(17077) on 2013-01-30 12:03:08 (Show Source):

You can put this solution on YOUR website!

First recognize that there is no difference between

and

.

Then

Solve for

Hints: The LCD is 24, and 34 divided by 17 is 2.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

test/708267: i have a test on fractions and i am stuck on my 15th question could you please help me and show me how we how i can show my workings out,
the question is - 4/5 - 7/10 + 1/2 =
1 solutions

Answer 436038 by solver91311(17077) on 2013-01-30 11:58:28 (Show Source):

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Multiply the first fraction by 1 in the form of

. Multiply the third fraction by 1 in the form of

. The result will be the sum of three fractions all of which have the same denominator. Add the numerators and reduce the result to lowest terms.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Graphs/708269: Please help me answer this: What is the equation of the horizontal line through (5,8)
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Answer 436028 by solver91311(17077) on 2013-01-30 11:37:13 (Show Source):

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The equation of any horizontal line is

where

is the

-coordinate of any point contained in the line.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Travel_Word_Problems/708270: A woman traveled 2,438 miles in 19 hours 20 minutes. Find the average speed of her flight in miles per hour.
1 solutions

Answer 436026 by solver91311(17077) on 2013-01-30 11:35:23 (Show Source):

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Speed is distance divided by time. Hint: 20 minutes is 1/3 of an hour. So divide 2438 by 58/3. Round to the nearest whole mile per hour because the least precise measurement given was to the nearest whole mile.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Square-cubic-other-roots/706048: The following terms √3x + √9x + √27x + ... form a pattern that continues until the sixth is found.
1. Compute the sum of all six terms...which I have done.
2. By investigating the pattern further, develop a system that will enable you to find the sum of 12 such terms without actually writing them. I have written out the twelve terms and I cannot figure out a system. I would love a hint or clue to help me solve this.
1 solutions

Answer 434965 by solver91311(17077) on 2013-01-24 22:23:55 (Show Source):

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This is the most interesting problem I've seen on this site in a long time.

The first thing to do is to factor

out of all of the terms, so that just becomes a factor in the answer.

Then you have a sum of radicals. Note that each of the radicands is one power of 3 larger than the previous. The pattern becomes evident when you replace the radical with a fractional exponent.

and so on...

So you could write the first six terms thus:

Now if you rearrange the terms so that the rational terms are in one group and the irrational terms are in another group:

Then factor the radical out of the first grouping (putting the

back in):

The sum becomes trivial

So for 12 terms:

But then we get to make it even simpler because

from which we can derive

So your 12 term sum becomes

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Systems-of-equations/706041: You plan to mail surveys to different households. A box of 50 envelopes cost $3.50, and a postage stamp cost $.44. How much will it cost you to mail 40 surveys.
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Answer 434950 by solver91311(17077) on 2013-01-24 21:29:33 (Show Source):

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Why did you submit the same problem twice?

Systems-of-equations/706043: You plan to mail surveys to different households. A box of 50 envelopes cost $3.50, and a postage stamp cost $.44. How much will it cost you to mail 400 surveys.
1 solutions

Answer 434949 by solver91311(17077) on 2013-01-24 21:28:10 (Show Source):

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Why did you submit the same problem twice?

sets-and-operations/706013: Write the compound statement in words. Let p: Joe has an iPad. q: Brie has a MacBook; ~p
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Answer 434923 by solver91311(17077) on 2013-01-24 20:31:41 (Show Source):

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Joe does not have an iPad

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Functions/706017: please help me identify the domain of this function: g(x)=3x/x^2-36
1 solutions

Answer 434921 by solver91311(17077) on 2013-01-24 20:28:36 (Show Source):

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The domain of a rational function is the set of real numbers excluding any value that makes the denominator equal to zero. Set the denominator polynomial equal to zero and solve for the two roots. The domain of the original function is the set of real numbers excluding those to roots.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Triangles/706010: Triangle DEF is isosceles. Angle D measures 20 degrees. what is the measure of angle E in degrees?

1 solutions

Answer 434918 by solver91311(17077) on 2013-01-24 20:25:29 (Show Source):

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Depends.

You don't bother to mention which segment, DE, EF, or FD is the base, nor do you say which angle, D, E, or F is the vertex angle.

So you either have a vertex angle D that measures 20 degrees and two other angles that are equal in measure and the sum of all three is 180 degrees, or angle E has to be congruent to angle D.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Quadratic-relations-and-conic-sections/706005: how can i find the focus/foci and vertex/vertices
x^2-4y^2-2x+16y=20
this is how far i have gotten, but i am not sure if it is right so far
x^2-4y^2-2x+16y=20
(x^2-2x+1)-4(y^2+4y+4)=20+1+4
(x-1)^2/25-4(y+4)^2/25=25/25
(x-1)^2/25-4(y+4)^2/25=1
please help. thank you.
1 solutions

Answer 434916 by solver91311(17077) on 2013-01-24 20:14:24 (Show Source):

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Note the -4 coefficient OUTSIDE the parentheses so the 1st degree y term has to have a coefficient of -4 (-4 times -4 is +16), then in order to complete the square inside the parentheses you need a +4, and +4 times -4 is -16. What you add to the left must be added to the right, hence the -16 in the RHS.
From there:

and

Can you take it from there?

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

test/706001: (X+3)squared-5(x+3)+4=0
1 solutions

Answer 434909 by solver91311(17077) on 2013-01-24 19:59:17 (Show Source):

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X and x are not the same thing.

You didn't follow the instructions to describe the entire problem. What do you want to do with this?

You didn't follow the instructions to describe what you have done so far.

We put as much work into answering your questions as you put into asking them.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

percentage/705966: 1. Solve the following system of equations using Gaussian elimination method. If there are no solutions, type "N" for both x, y and z. If there are infinitely many solutions, type "z" for z, and expressions in terms of z for x and y.

0x+7y+0z=-1
5x−5y+6z=-1
−5x+1y+3z=6 ..?
2. Phyllis invested 47000 dollars, a portion earning a simple interest rate of 4 percent per year and the rest earning a rate of 6 percent per year. After one year the total interest earned on these investments was 2620 dollars. How much money did she invest at each rate?
3.A movie theater charges $ 10 for adults and $ 7 for seniors. On a particular day when 347 people paid an admission, the total receipts were $ 2518. Round your answers to the nearest integers.. How many who paid were adults? .. How many who paid were seniors..?
1 solutions

Answer 434905 by solver91311(17077) on 2013-01-24 19:48:47 (Show Source):

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 0        	7        	0        	1        
 5          -5        	6              -1        
-5        	1        	3        	6        

Swap row 1 and row 2
			
5        	-5        	6        	-1        
0        	7        	0        	1        
-5        	1        	3        	6        

R2/7 to R2
			
5        	-5        	6        	-1        
0        	1        	0        	   1/7  
-5        	1        	3        	6        
	
R1 + R3 to R3
		
5        	-5        	6        	-1        
0        	1        	0        	   1/7  
0        	-4        	9        	5        
		
R1/5 to R1
	
1        	-1        	1   1/5  	-   1/5  
0        	1        	0        	   1/7  
0        	-4        	9        	5        
	
R1 + R2 to R1
		
1        	0        	1   1/5  	-   2/35 
0        	1        	0        	   1/7  
0        	-4        	9        	5        
		
4R2 + R3 to R3
	
1        	0        	1   1/5  	-   2/35 
0        	1        	0        	   1/7  
0        	0        	9        	5   4/7  
		
R3/9 to R3
	
1        	0        	1   1/5  	-   2/35 
0        	1        	0        	   1/7  
0        	0        	1        	  13/21 
	
-6/5*R3 + R1 to R1
		
1        	0        	0        	-   4/5  
0        	1        	0        	   1/7  
0        	0        	1        	  13/21

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Length-and-distance/705960: Germaine walks at the rate of 10 feet every five seconds while Nolan walks at the rate of 15 feet every five seconds. If Germaine has a head start of 25 feet, after how many seconds will they be at the same spot?
1 solutions

Answer 434893 by solver91311(17077) on 2013-01-24 19:10:30 (Show Source):

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The difference in their speeds is 5 feet per 5 seconds, or 1 foot per second. How long will it take Nolan to cover the 25 foot head start at 1 foot per second?

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

absolute-value/705965: what is X if 10 minus 2, times the absolute value of 5 minus X, is 3
1 solutions

Answer 434892 by solver91311(17077) on 2013-01-24 19:07:26 (Show Source):

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Presuming you mean:

Add -10 to both sides.

Multiply both sides by

Then

Solve both for

. Check both answers.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

test/705964: -4/5=2b
b=?
1 solutions

Answer 434888 by solver91311(17077) on 2013-01-24 18:57:55 (Show Source):

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Multiply both sides by

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Inequalities/705963: How do you do x^2 + 5x +6 = 0
& b^2 - 7b - 18 = 0
1 solutions

Answer 434887 by solver91311(17077) on 2013-01-24 18:56:55 (Show Source):

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How do you do what to them?

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

Age_Word_Problems/705962: You can buy 5 small pizzas for the same price as 3 small pizzas and ten $1 drinks. How much does each pizza cost?
1 solutions

Answer 434886 by solver91311(17077) on 2013-01-24 18:55:45 (Show Source):

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2 of the pizzas must be the same value as the 10 drinks.

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it

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