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Miscellaneous_Word_Problems/181456: A grocer sells potatoes in 4pound bags and 3 pound bags. He sold 594 bags of potatoes on Thursday.. He sold the same number of 4 pound bags as he did 3 pound bags. How many of each did he sell ? 1 solutions
Answer 136066 by josmiceli(9817) on 2009-02-11 00:36:29 (Show Source):
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Miscellaneous_Word_Problems/181457: The state of Nevada has an area of 286,367 square kilometers. In 2005, Nevada had an estimated population of 2,414,807 people. Approximately how many people per square kilometer is this? 1 solutions
Answer 136065 by josmiceli(9817) on 2009-02-11 00:34:03 (Show Source):
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Proportions/181454: This question is from textbook
i do not understand scales for pre algebra here is my question:
Actual size:30ft
drawing size: 6 inches 1 solutions
Answer 136064 by josmiceli(9817) on 2009-02-11 00:29:57 (Show Source):
You can put this solution on YOUR website!6 in on a map represents 30 ft on the ground
It's like you got into a helicopter and climbed
higher and higher until something on the
ground that was 30 ft long looked 6 in long
If you got even higher, it might look 1/2 in long
All the scale is saying is:
How does 6 in compare with 30 ft?
How many inches are in 30 ft?
30 ft x 12 in/ft = 360 in
The scale is 6 in / 360 in, or
1 in / 60 in
Note that feet and inches are like apples and oranges.
You can't compare them directly
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Systems-of-equations/181451: Lorena bought 10 packs of styrofoam cups for the graduation dance. a pack of fifty 12-oz cups costs $1.80 and apack of fifty 16-oz cups costs $2.40. Lorena paid a total of $21.60 excluding tax. How many packs of each size cup did she buy? 1 solutions
Answer 136060 by josmiceli(9817) on 2009-02-10 23:31:07 (Show Source):
You can put this solution on YOUR website!Let  = the number of packs of 12 oz cups she bought
Let  = the number of packs of 16 oz cups she bought
given:
(1) 
(2) 
Multiply both sides of (1) by 180 and subtract from (2)
(2) 
(1)

and, since
(1)

She bought 4 packs of 12 oz cups and
6 packs of 16 oz cups
check answer:
(2) 
(2)

OK
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Travel_Word_Problems/181114: two military squads are 26 miles apart. they plan to rendezvous at some intermediate point. if one squad hikes 2/3 mph faster than the other, and they meet in 3 hrs, what is the rate of the faster squad? 1 solutions
Answer 135791 by josmiceli(9817) on 2009-02-09 17:00:40 (Show Source):
You can put this solution on YOUR website!Let  = the rate of the slower squad
Let  = the distance the slower squad travels in 3 hrs
given:
The rate of the faster squad is

The distance the faster squad travels in 3 hrs is

---------------------
For slower squad:
(1) 
For faster squad:

(2) 
Subtract (1) from (2)
(2) 
(1)
 mi/hr
The rate of the faster squad is
 mi/hr
The faster squad's rate was 4.67 mi/hr
check answer
 mi
 mi/hr
OK
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Radicals/181124: sqrt40a^3b^4
It asks that i right the expression in simplest radical form. since 40 and 3 has no sqrt i dnt no where to begin. Thanks for any help. 1 solutions
Answer 135785 by josmiceli(9817) on 2009-02-09 16:36:34 (Show Source):
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Equations/181058: Suppose that you are taking a course that has 4 tests. The first three tests are for 100 points each and the fourth test is for 200 points. To get an B in the course, you must have an average of at least 80 percent on the 4 tests. Your scores on the first 3 tests were 83, 75, and 91. What is the minimum score you need on the fourth test to get an B for the course? 1 solutions
Answer 135711 by josmiceli(9817) on 2009-02-09 10:12:24 (Show Source):
You can put this solution on YOUR website!I'll call the points scored on the tests a, b, c, and d
Points scored on a, b, and c are:

The total possible points for the 4 tests are

In order to average  %,

You must score 151 points out of 200 to get a B
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Polynomials-and-rational-expressions/181059: I am homeschooled with the School of Tomorrow. I have no teacher, and am struggling with factoring trinomials, particularly coefficients greater than one and complex factoring. Right now I am trying to solve Please help me! 1 solutions
Answer 135705 by josmiceli(9817) on 2009-02-09 10:01:27 (Show Source):
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Quadratic_Equations/181025: Joe has a collection of nickles and dimes that is worth $6.05. If the number of dimes was doubled and the number of nickles was decreased by 10,the vlue of th ecoins would be $9.85. How many dimes does he have? 1 solutions
Answer 135694 by josmiceli(9817) on 2009-02-09 00:47:54 (Show Source):
You can put this solution on YOUR website!Let  = the number of nickels
Let  = the number of dimes
given:
 (in pennies)

(1) 
(2) 
Subtract (2) from (1)
(1) 
(2)

He has 43 dimes
And, since
(2)

check answer:
(1)

OK
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Finance/181026: This question is from textbook Algebra 1 COncepts and skills
I dont really understand how to find the balance or what the interest is ?
using this formula y = C(1+r)t 1 solutions
Answer 135692 by josmiceli(9817) on 2009-02-09 00:37:24 (Show Source):
You can put this solution on YOUR website!The formula for interest is:
 where
 = principle
 = the rate
 = time
Example:
You invest $1,000 at an annual interest rate of 3%
After 2 years:

So, you make $60 in interest after 2 years
--------------------
You got the formula wrong. It should be:

To understand, you should factor it.

What this says is:
(Principle + Interest) = (Principle) + (Interest)
The  is principle
The  is interest
-------------------------
Continuing with the example,
You invest $1,000 at an annual interest rate of 3% for 2 years
 is what you invested + the interest the money earned
after 2 years at 3%
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Word_Problems_With_Coins/180987: This question is from textbook College Algebra
Mary has $4.40 in nickles,dimes and quarters. She has four more dimes than quarters and twice as many nickles as dimes. How many coins of each type does she have? 1 solutions
Answer 135673 by josmiceli(9817) on 2009-02-08 21:07:05 (Show Source):
You can put this solution on YOUR website!Let  = number of nickels
Let  = number of dimes
Let  = number of quarters
given:
(1) 
(1) 
(2) 
(3)  (in cents)
Substitute  in (1) and  in (2) for
 and  in (3)
(3)

and
(1)

and
(2)

She has 30 nickels, 15 dimes, and 11 quarters
check:
(3)  (in cents)

OK
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Quadratic_Equations/180998: 3. Walt made an extra $12,000 last year from a part-time job. He invested part of the money at 7% and the rest at 9%. He made a total of $970 in interest. How much was invested at 7%? 1 solutions
Answer 135672 by josmiceli(9817) on 2009-02-08 20:51:31 (Show Source):
You can put this solution on YOUR website!Let  = amount invested @ 7%
Let  = amount invested @ 9%
given:
(1) 
(2) 
Multiply both sides of (2) by 
and subtract from (1)
(1) 
(2) 
And, subtracting:
(1) 
(2)

And, since
(2)

$5500 was invested @ 7%
check:
(1)

OK
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Human-and-algebraic-language/180802: This question is from textbook Beginning Algebra with Applications
A postal clerk sold some $.34 stamps and some $.23 stamps. Altogether, 15 stamps were sold for the total cost of $4.44. How many of each type of stamp were sold? 1 solutions
Answer 135533 by josmiceli(9817) on 2009-02-07 20:40:15 (Show Source):
You can put this solution on YOUR website!Let the number of $.34 stamps = 
Let the number of $.23 stamps = 
given:
(1) 
(2) 
Multiply both sides of (1) by  and
subtract from (2)
(2) 
(1) 
------------------------------
(2) 
(1)

And, since
(1)

9 of the $.34 stamps were sold and
6 of the $.23 stamps were sold
check:
(2)

OK
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Trigonometry-basics/180794: This question is from textbook Analytic Trigonometry
Standing on the bank of a river, a surveyor measures the angle to the top of a tree on the opposite bank to be 23 degrees. He backs up 45ft and remeasures the angle to the top of the tree at 18 degrees. How wide is the river? 1 solutions
Answer 135530 by josmiceli(9817) on 2009-02-07 19:45:06 (Show Source):
You can put this solution on YOUR website!Let the width of the river =  ft
Let the height of the tree =  ft
given:
(1) 
(2) 
These are 2 equations with 2 unknowns, so
they should be solvable

(1) 
(2) 
----------------------------
Multiply both sides of (1) by 
Multiply both sides of (2) by 
(1) 
(2) 
(2) 
Subtract (2) from (1)
(1) 
(2)

The river is 146 ft 9 in wide
check answer:
(2)
 ft the height of the tree
(1)
 close enough
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Quadratic_Equations/180687: I need help please show me an example of a complex roots equation. Thanks 1 solutions
Answer 135421 by josmiceli(9817) on 2009-02-06 21:02:09 (Show Source):
You can put this solution on YOUR website!Suppose the roots are  and  , then
the equation can be factored into
 and  , so

Note that if you replace  by either  or  ,
Then the equation is solved
Now multiplying the factors:

(note that  and  )
 is the equation to find roots
 is the complete complex roots equation
There are 2 complex roots to this equation,
 and 
Graphing it, you can see it doesn't intersect the x-axis, where
real roots would be:
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Rate-of-work-word-problems/180686: Jim can fill a pool carrying buckets of water in 30 minutes. Sue can do the same job in 45 minutes. Tony can do the same job in 1 ½ hours. How quickly can all three fill the pool together? 1 solutions
Answer 135417 by josmiceli(9817) on 2009-02-06 20:40:50 (Show Source):
You can put this solution on YOUR website!In words:
Let  = number of hours for Jim, Sue, and Tony to
fill pool working together
Jim's rate of filling + Sues rate of filling + Tony's rate of filling =
rate of all 3 filling pool together

Multiply both sides by
 hr
All 3 filling pool together can do the job in 15 min
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Linear-systems/180671: This question is from textbook Algebra 1
2m + n = 1
m - n = 8 1 solutions
Answer 135400 by josmiceli(9817) on 2009-02-06 17:22:37 (Show Source):
You can put this solution on YOUR website!There are 2 equations and 2 unknowns,
so it is solvable. If there were more
unknowns than equations it would be
unsolvable
(1) 
(2) 
Just add the equations

Divide both sides by

As long as I do the same thing to both
sides, the equation is still true.
Put  back into (2)

Subtract  from both sides

Multiply both sides by

The solution is  and
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Coordinate-system/180585: A motorboat went 10 miles upstream in 1 hour. The return trip took only 30 minutes. Assume that the "water speed" and the current speed were constant during both parts of the trip. Find the water speed of the boat and the current speed. 1 solutions
Answer 135382 by josmiceli(9817) on 2009-02-06 12:17:26 (Show Source):
You can put this solution on YOUR website!Let  = the speed of the boat in still water
Let  = the speed of the current
For the trip upstream:
(1) 
For the trip downstream:
(2) 
given:
 mi
 mi
 hr
 hr
upstream:

------------------------
(1) 
(1) 
(1) 
(1) 
and
(2) 
(2) 
(2) 
(2) 
-------------------------------
Subtract (2) from (1)
(1) 
(2) 
(3)

Now I can rewrite (1)
(1) 
(1) 
(1)
 mi/hr
and, since
(1) 
(1) 
(1)  mi/hr
The speed of ther boat in still water is 15 mi/hr
The speed of the current is 5 mi/hr
check:
(2)

OK
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Rational-functions/180611: A circular table is to be made that will have a top covered with material that costs $3.50 per square foot. The covering is to cost no more than $60. What is the maximum radius for the top of the table? 1 solutions
Answer 135379 by josmiceli(9817) on 2009-02-06 11:53:03 (Show Source):
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Graphs/180616: please help me solve this problem
Solve the equation 3x - 14 = 1 1 solutions
Answer 135375 by josmiceli(9817) on 2009-02-06 11:39:43 (Show Source):
You can put this solution on YOUR website!
You MUST do the same thing to BOTH sides of the equation
If you do that, you won't change the truth of the equation,
namely that one side is equal to the other
OK, I'll subtract  from both sides
 (note that in this step, I'm just rewriting it,
not doing the same thing to both sides)
 (again, I'm just rewriting it)
Now I will add  to both sides
 (just rewriting it)
Now I will divide both sides by
 (I did the same thing to both sides)
 answer
(note that  is the same as
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Trigonometry-basics/180507: Write the trig function as an algebraic expression: sin(2arctanx)
PLEASE HELP ME!!! I really don't know what to do. 1 solutions
Answer 135306 by josmiceli(9817) on 2009-02-05 21:17:32 (Show Source):
You can put this solution on YOUR website!You have to say this one in a way that makes sense
In words:
First, "arctan(x)" means "the angle whose tangent is x"
Therefore, "2*arctan(x)" means twice the angle whose tangent is x"
Now I can read the whole thing as:
"the sine of twice the angle whose tangent is x"
If the tangent is  , then the sine is 
and the cosine is 
The double angle formula for sine is:
 answer
Suppose the angle was 45 degrees. Then  and
 and this is true
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percentage/180544: In trying to find what 8% of 5% is, would i need to convert both percentages into a fraction? What is the process I would complete to find the answer 1 solutions
Answer 135302 by josmiceli(9817) on 2009-02-05 20:55:35 (Show Source):
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Expressions-with-variables/180513: 5x-y=-18
4x+2y=92
These are both the same problem.I don't get how to do these problems.Could you explain to me how to do this type of problem please? 1 solutions
Answer 135293 by josmiceli(9817) on 2009-02-05 20:31:31 (Show Source):
You can put this solution on YOUR website!What they are is 2 equations with 2
unknowns, so I can assume you are to
solve for  and 
(1) 
(2) 
They should be solvable. If I graph them,
they are 2 intersecting straight lines
and the solution, (x,y) is where they
intersect. I'll graph them

Looking at the graph, the intersection is at about  ,
 , so the solution would be (4,38)
Now I'll find the actual solution
(1) 
(2) 
Multiply both sides of (1) by  and add the equations
(1) 
(2)

Now put this value of  back into (1)
(1)

So, I guessed right. The solution is
(4,38), or in other words,
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percentage/180528: Express the following percent in decimal and in fraction form (in lowest terms).
0.02% = I understand that it's decimal form is 0.0002 but I don't understand why it's fraction format would not be 0.02/100 instead of 1/5,000. 1 solutions
Answer 135280 by josmiceli(9817) on 2009-02-05 20:11:22 (Show Source):
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