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jorel1380 answered: 2517 problems
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Equations/504666: Pc sells regular keyboards for $84 and wireless keyboards for $105. Last week the store sold three times as many regular keyboards as wireless. If total keyboard sales were $4,998, how many of each type were sold?
1 solutions

Answer 339673 by jorel1380(2518) About Me  on 2011-09-26 14:17:55 (Show Source):
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84(3m)+105(m)=4998
357m=4998
m=14
3m=42
PC sold 42 regular keyboards and 14 wireless keyboards..


Money_Word_Problems/504656: Jackie invests $25,000, part as a 5.5% annual interest and the balance at 8.3% annual interest. How much is invested at each rate if Jackie receives a 1-year interest payment of $1571?
1 solutions

Answer 339671 by jorel1380(2518) About Me  on 2011-09-26 14:15:17 (Show Source):
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.055m+.083(25000-m)=1571
55m+83(25000-m)=1571000
55m+2075000-83m=1571000
2075000-1571000=83m-55m=28m
28m=504000
m=18000
Jackie invested $18000 at 5.5% interest and $7000 at 8.3% interest..


Mixture_Word_Problems/504652: How much 10% solution and how much 45% solution should be mixed together to make 100 gallons of 25% solution?
1 solutions

Answer 339670 by jorel1380(2518) About Me  on 2011-09-26 14:11:17 (Show Source):
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100 x.25=25 gallons extract
.1m+.45(100-m)=25
.1m+45-.45m=25
20=.35m
20/.35=m
m=57.143
100-m=42.857
You need 57.143 gals of 10% solution and 42.857 gals of 45% solution for your mix..


Equations/504592: There were 886 deer caught and tagged in a conservatory. Later 350 more were caught, out of those 350, 175 were already tagged. How many deer are in the conservatory?
I can do math but I am seriously lacking on how to form the equation. I think the equation should look like this; 305/175=886/x. However when I do the math I get a crazy answer. Help.
1 solutions

Answer 339648 by jorel1380(2518) About Me  on 2011-09-26 12:04:48 (Show Source):
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175/350:886/n
175n=310100
n=310100/175=1772
There are approximately 1772 deer in the conservatory..


Mixture_Word_Problems/504591: I have been stuck on this word problem for forever! Please help me.
Army requirements call for 55 coffee grounds per quart of coffee. The cooks have one barrel of coffee with 67.5 grounds per quart in it and another barrel with 45 grounds per quart in it. How many quarts of each should they mix together to make up 1 quarts?
the answer is: eight quarts of the 67.5 grounds/quart and ten quarts of the 45 grounds/quart.
I just can't figure out how they got these answers. I've gotten a set of answers of my own that will work, but I would like to know how to get these answers.

thanks
1 solutions

Answer 339645 by jorel1380(2518) About Me  on 2011-09-26 12:01:15 (Show Source):
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67.5m+45n=55(m+n)
67.5m+45n=55m+55n
12.5m=10n
1.25m=1n
m=.8n
For every part of 45 ground coffee, you need to use .8 parts of 67.5 ground coffee to get 55 ground coffee:
n+.8n=1
1.8n=1
n=1/1.8=.5556
.5556(45)+.4444(67.5)=25.002+29.997=54.9999.


Probability-and-statistics/504581: A local organization is having a raffle drawing to give away five $100 gift certificates. If 155 people enter the raffle by each buying exactly one ticket, how many different groups of 5 winners can there be?
1 solutions

Answer 339640 by jorel1380(2518) About Me  on 2011-09-26 11:40:51 (Show Source):
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155C5=155x154x153x152x151x150!/5x4x3x2x150!=698 526 906 different combinations of winners..


Human-and-algebraic-language/504588: The difference between nine times a number ans six more then two times the number.
What is the algebraic expression?
What is the simplified expression?
I came up with 9x-(2x+6) for the algebraic expression and 7x-6 for simplified expression.
1 solutions

Answer 339638 by jorel1380(2518) About Me  on 2011-09-26 11:37:06 (Show Source):


Miscellaneous_Word_Problems/504577: to win the lotto in one state, one must correctly select 8 numbers from a collection of 65 numbers (one through 65)the order does not matter. how many different selections are possible?
1 solutions

Answer 339637 by jorel1380(2518) About Me  on 2011-09-26 11:35:53 (Show Source):
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65C8=65x64x63x62x61x60x59x58x57!/8x7x6x5x4x3x2x57!=5 047 381 560 different selections possible..


Miscellaneous_Word_Problems/504576: The net income y(in millions of dollars)of Pet Products Unlimited from from 1997 to 1999 is given by the equation y = 9x2+15x+52 where x represents the number of years after 1997. Assume this trend continues and predicts the year in which Pet Products Unlimited's net income will be $598 million.
1 solutions

Answer 339636 by jorel1380(2518) About Me  on 2011-09-26 11:29:35 (Show Source):
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598=9x2+15x+52
9x2+15x-546=0
3x2+5x-182=0
(3x+26)(x-7)=0
x=-26/3 or 7
Throwing out the negative answer, we get x=7 years after 1997 which is 2004..


Mixture_Word_Problems/504569: Please help me with this equation: A company has two molds to form tires. One mold has a setup cost of $1,000 and the other has a setup cost of $3,000. The cost to make each tire with the first mold is $15, and the cost to make each tire with the second mold is $10.
*Find the break point?
1 solutions

Answer 339634 by jorel1380(2518) About Me  on 2011-09-26 11:24:09 (Show Source):
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1000+15x=3000+10x
5x=2000
x=400
The point at which the processes are equal is at 400 tires..


Numbers_Word_Problems/504566: In triangle A,B,C the measure of B is twice the measure of angle A the measure of angle C is 80 more than that of angle A. find the angle measures.
1 solutions

Answer 339633 by jorel1380(2518) About Me  on 2011-09-26 11:22:52 (Show Source):
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m+2m+m+80=180
4m=100
m=25
Angle A is 25 degrees
Angle B is 50 degrees
Angle C is 105 degrees..


Mixture_Word_Problems/504565: Please help me with this equation: A restaurant manager buys 100lb of hambure and 50lb of steak for a total cost of $490. A second purchase at the same prices, includes 150lb of hambureger and 100lb of steak. Total cost is 860. Find the price of 1lb of steak.
1 solutions

Answer 339632 by jorel1380(2518) About Me  on 2011-09-26 11:21:25 (Show Source):
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100m+50n=490
150m+100n=860
200m+100n=980
50m=980-860=120
m=120/50=$2.40 per lb of hamburger
n=$5.00 per lb. of steak..


Mixture_Word_Problems/504564: Please help me with this equation: Flying with the wind, a small plane required 2h to fly 150 miles. Against the wind, it took 3h to fly the same distance. Find the rate of the wind.
1 solutions

Answer 339631 by jorel1380(2518) About Me  on 2011-09-26 11:18:32 (Show Source):
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150/2=75 mph
150/3=50 mph
75+50/2=125/2=62.5 mph average in still air
75-62.5=62.5-50=12.5 mph average wind speed..


Miscellaneous_Word_Problems/504563: Using a phone card to make a long distance call costs a flat fee of $0.36 plus $0.34 per minute starting with the first minute. What is an equation of the y=ax+b for this situation?
1 solutions

Answer 339630 by jorel1380(2518) About Me  on 2011-09-26 11:15:57 (Show Source):
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y=.34x + .36..


Mixture_Word_Problems/504560: Please help me answer this question: how many milliliters of pure water must be added to 100ml of a 4% salt solution to make a 2.5% salt solution?
1 solutions

Answer 339629 by jorel1380(2518) About Me  on 2011-09-26 11:15:16 (Show Source):
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100x.04=4ml salt
.025m=4
m=4/.025=160
Since you already have 100 ml of solution, you need to add 60 ml of pure water to get a 2.5% solution..


Numbers_Word_Problems/504559: The difference of two numbers is twice the first number.
1 solutions

Answer 339628 by jorel1380(2518) About Me  on 2011-09-26 11:12:46 (Show Source):
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n-m=2m
n=3m..


Triangles/501815: if two sides of a triangle are 10 and 9, what would the range of the third side be?
1 solutions

Answer 338677 by jorel1380(2518) About Me  on 2011-09-21 14:11:41 (Show Source):
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sqrt(81+100)=sqrt (181)=between 13 and 14.., assuming it's a right triangle..


Quadratic_Equations/501814: I need help solving the following... I have to simplify and then solve using the quadratic formula but I am getting stuck something is not right.. I have started to simplify but end up canceling out the 3x but don't I need that??? Grrrr Help please!!!
x(x+3)-2=3x+7
1 solutions

Answer 338675 by jorel1380(2518) About Me  on 2011-09-21 14:10:04 (Show Source):
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x(x+3)-2=3x+7
x2+3x-2=3x+7
x2-9=0
x2=9
x=3 or -3..


Linear_Equations_And_Systems_Word_Problems/501812: Christine went shopping and bought each of her nine nephews a gift, either a video costing $14.95 or a CD costing $16.88. She spent $148.06 on the gifts. How many videos and how many CDs did she buy?
1 solutions

Answer 338672 by jorel1380(2518) About Me  on 2011-09-21 14:08:33 (Show Source):
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m+n=9
14.95m+16.88n=148.06
1495m+1688n=14806
1495m+1495n=13455
193n=1351
n=7
m=2
Christine bought 2 videos and 7 CD's..


Miscellaneous_Word_Problems/501810: if 1 pill weighed .2 grams, how many pills could could be made out of 1 kg
1 solutions

Answer 338670 by jorel1380(2518) About Me  on 2011-09-21 14:05:29 (Show Source):
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1000 grams/.2=5000 pills possible out of 1 kilogram..


Trigonometry-basics/501808: Please show me how to solve this. (x-7)squared=(x+7)squared+168
1 solutions

Answer 338667 by jorel1380(2518) About Me  on 2011-09-21 14:03:03 (Show Source):
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(x-7)2=(x+7)2+168
x2-14x+49=x2+14x+49+168
-168=28x
x=-6..


Travel_Word_Problems/501797: if the boats in William's fleet averaged four miles an hour how long would it have taken to cross 200 km

1 solutions

Answer 338665 by jorel1380(2518) About Me  on 2011-09-21 13:56:42 (Show Source):
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4 mph=4x1.6 kilo/mile=6.4 k/hr
200/6.4=31.25 hours..


test/497981: 2n-7=5n-10
1 solutions

Answer 336877 by jorel1380(2518) About Me  on 2011-09-14 20:00:07 (Show Source):
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2n-7=5n-10
3=3n
n=1..


Linear_Equations_And_Systems_Word_Problems/497978: At a bake, it cost you $100 to make the baked goods.if you charge $2 for each goodie write an equation that models your total profit.
1 solutions

Answer 336876 by jorel1380(2518) About Me  on 2011-09-14 19:59:14 (Show Source):
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P=2n-100 where P is profit and n is the amount of goodies sold..


Rectangles/497969: the length of a picture frame is 3in grater then the width. the perimiter is less then 52in. describe the dimension of the fram.
1 solutions

Answer 336874 by jorel1380(2518) About Me  on 2011-09-14 19:57:58 (Show Source):
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2(w+3)+2w<52
4w+6<52
4w<46
w<46/3
l<55/9..


Numbers_Word_Problems/497967: soybean meal is 16% protein and corn meal is 9% protein. How many pounds of each should be mixed together to get a 350-lb mixture that is 12% protein?
1 solutions

Answer 336872 by jorel1380(2518) About Me  on 2011-09-14 19:55:10 (Show Source):
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350x.12=42
m+n=350
.16m+.09n=42
16m+9n=4200
9m+9n=3150
7m=1050
m=150
You need 150 lbs. of soybean meal and 200 lbs. of corn meal for your mix..


Divisibility_and_Prime_Numbers/497962: A rectangular prism has a volume of 480 cm cubed. What is its volume if all of its dimensions are doubled?
1 solutions

Answer 336870 by jorel1380(2518) About Me  on 2011-09-14 19:52:01 (Show Source):
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If all sides are doubled, then each side represents 2x*2x*2x=8x the original volume-- so the volume is 480 x 8=3840 cm3..


Linear_Algebra/497951: Mrs. Boudon's dog dreams of chasing cats 2x+3 hours per day. How many hours does the dog dream in 4 weeks?
1 solutions

Answer 336868 by jorel1380(2518) About Me  on 2011-09-14 19:49:23 (Show Source):
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4 x 7 x (2x+3)=28(2x+3)=56x+84 times..


Age_Word_Problems/497955: The ratio of Ricardo's age and emily's age is 3:8 the difference in their ages is 15 years how old is emily?
1 solutions

Answer 336866 by jorel1380(2518) About Me  on 2011-09-14 19:47:32 (Show Source):
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8n-3n=15
5n=15
n=3
Emily=8 x 3 =24
Ricardo=3 x 3=9..


Mixture_Word_Problems/497948: What is the slope of 3x=1-4y
The x intercept
The y intercept
1 solutions

Answer 336865 by jorel1380(2518) About Me  on 2011-09-14 19:45:47 (Show Source):
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3x=1-4y
3x+4y=1
Solved by pluggable solver: DESCRIBE a linear EQUATION: slope, intercepts, etc
Equation 3+x+%2B+4+y+=+1 describes a sloping line. For any
equation ax+by+c = 0, slope is -a%2Fb+=+-3%2F4.
  • X intercept is found by setting y to 0: ax+by=c becomes ax=c. that means that x = c/a. 1/3 = 0.333333333333333.
  • Y intercept is found by setting x to 0: the equation becomes by=c, and therefore y = c/b. Y intercept is 1/4 = 0.25.
  • Slope is -3/4 = -0.75.
  • Equation in slope-intercept form: y=-0.75*x+0.25.


test/497148: A cell phone company charges $.35 for the first minute but only $.10 every minute after that. Why would the equation be, that Eric talked if the bill for the call was $5.45?
1 solutions

Answer 336674 by jorel1380(2518) About Me  on 2011-09-13 19:56:30 (Show Source):
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.35+.1n=5.45
35+10n=545
10n=510
n=51..