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Equations/306913: A grocer at a specialty store is mixing coffee worth $6 per pound with coffee worth $8 per pound. He wants to obtain 144 pounds of coffee worth $7.50 per pound.How much of each coffee should he use?
Amount of coffee X=108
Amount of coffee Y=36
1 solutions
Answer 219569 by checkley77(12569)   on 2010-05-20 18:53:18 (Show Source):
You can put this solution on YOUR website!8x+6(144-x)=7.50*144
8x+864-6x=1,080
2x=1,080-864
2x=215
x=216/2
x=108 pounds of $8 coffee is uded.
144-108=36 pounds of $6 coffee is used.
Proof:
8*108+6*36=7.50*144
864+216=1,080
1,080=1,080
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Quadratic_Equations/306915: In baseball a players batting average is the ratio of hits to the number of the times he or she has batted. Thus, if the player has an average of .300, it means he or she got 300 hits in 1000 at bats. In order to have an average of .300, how many hits would the batter have to get in 400 times a bat?
1 solutions
Answer 219567 by checkley77(12569) on 2010-05-20 18:45:40 (Show Source):
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Rectangles/306550: For the first six years, the loan value of a Corvette is determined by the formula
V = – 4000a + 50000, where V is the value and a is the age of the car in years. What was its original value? What is its value when it is 5 years old?
1 solutions
Answer 219374 by checkley77(12569) on 2010-05-19 20:26:55 (Show Source):
You can put this solution on YOUR website!V = – 4000a + 50000
YEAR ZERO:
V=-4000*0+50,000
V=$50,000 ANS. FOR THE ORIGINAL VALUE.
YEAR 5:
V=-4,000*5+50,000
V=-20,000+50,000
V=$30,000 ANS. FOR THE VALUE IN YEAR 5.
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Mixture_Word_Problems/306552: It is necessary to have a 40% antifreeze solution in the radiator of a certain car. The radiator now
has 50 liters of 20% solution. How many liters of this should be drained and replaced with 100%
antifreeze to get the desired strength?
1 solutions
Answer 219371 by checkley77(12569) on 2010-05-19 20:19:46 (Show Source):
You can put this solution on YOUR website!x+.20(50-x)=.40*50
x=10-.20x=20
.8x=20-10
.8x=10
x=10/.8
x=12.5 liters need to be drained & filled with 100% antifreeze.
Proof:
12.5+.20(50-12.5)=.40*50
12.5+.20*37.5=20
12.5+7.5=20
20=20
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Mixture_Word_Problems/306553: In a chemistry class, 9 liters of a 4% silver iodide solution must be mixed with a 10% solution to get
a 6% solution. How many liters of the 10% solution are needed?
1 solutions
Answer 219368 by checkley77(12569) on 2010-05-19 20:04:58 (Show Source):
You can put this solution on YOUR website!.04*9+.10x=.06(9+x)
.36+.10x=.54+.06x
.10x-.06x=.54-.36
.04x=.18
x=.18/.04
x=4.5 liters of 10% solution is used.
Proof:
.04*9+.10*4.5=.06(9+4.5)
.36+.45=.06*13.5
.81=.81
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Money_Word_Problems/306554: Mardi received an inheritance of $60,000. She invested part at 10% and deposited the remainder in
tax-free bonds at 8%. Her total annual income from the investments was $5800. Find the amount
invested at 10%.
1 solutions
Answer 219367 by checkley77(12569) on 2010-05-19 20:00:02 (Show Source):
You can put this solution on YOUR website!.10x+.08(60,000-x)=5,800
.10x+4,800-.08x=5,800
.02x=5,800-4,800
.02x=1,000
x=1,000/.02
x=50,000 amount invested @ 10%.
60,000-50,000=10,000 amount invested @ 8%.
Proof:
.10*50,000+.08*10,000=5,800
5,000+800=5,800
5,800=5,800
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Money_Word_Problems/306555: Roberto invested some money at 7%, and then invested $2000 more than twice this amount at 10%.
His total annual income from the two investments was $3980. How much was invested at 10%?
1 solutions
Answer 219365 by checkley77(12569) on 2010-05-19 19:55:23 (Show Source):
You can put this solution on YOUR website!.07x+.10(2x+2,000)=3,980
.07x+.20x+200=3,980
.27x=3,980-200
.27x=3,780
x=3,780/.27
x=$14,000 amount invested @ 7%
2*14,000+2,000=28,000+2,000=$30,000 invested @ 10%
Proof:
.07*14,000+.10*30,000=3,980
980+3,000=3,980
3,980=3,980
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Probability-and-statistics/306532: 1.69oz. bag of plain M&M's
Total in bag: 57
Red: 6 -11%
Yellow: 7 - 12%
Orange: 8 - 14%
Green: 13 - 23%
Blue: 16 - 28%
Brown: 7 - 12%
I reach into the bag and pull out a green M&M. What is the probability that I will choose a green M&M again?
1 solutions
Answer 219363 by checkley77(12569) on 2010-05-19 19:47:35 (Show Source):
You can put this solution on YOUR website!Having removed one grren M&M you have 12 green ones left out of a total of 56.
12/56=.214 or 21.4 % chance of getting a second green M&M.
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real-numbers/306540: If three times the smaller of two consecutive integers is added to four times the larger, the result is
95. Find the smaller integer.
1 solutions
Answer 219357 by checkley77(12569) on 2010-05-19 19:21:14 (Show Source):
You can put this solution on YOUR website!3x+4(x+1)=95
3x+4x+4=95
7x=95-4
7x=91
x=91/7
x=13 ans. for the smaller integer.
13+1=14 ans. for the larger integer.
Proof;
3*13+4*14=95
39+56=95
95=95
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Rectangles/306475: a rectangle has a perimeter of 22 and an area of 30. What is the length of the rectangle's diagonal?
1 solutions
Answer 219356 by checkley77(12569) on 2010-05-19 18:58:37 (Show Source):
You can put this solution on YOUR website!xy=30
x=30/y
2x+2y=22
2(30/y)+2y=22
60/y+2y=22
(60+2y*y)/y=22
60+2y^2=22y
2y^2-11y+60=0
2(y^2-y+30)=0
2(y-6)(y-5)=0
y-6=0
y=6 ans.
x*6=30
x=30/6
x=5 ans
y-5=0
y=5 ans.
x*5=30
x=30/5
x=6 ans.
Proof:
2*5+286=22
10+12=22
22=22
The diagonal:
5^2+6^2=c^2
25+36=c^2
61=c^2
c=sqrt61
c=7.81 ans. for the diagonal.
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Polynomials-and-rational-expressions/306483: Car A travels 180 miles in the same time it takes Car B to travel 120 miles. If one car is going 20 mph faster than the other car, find both speeds.
1 solutions
Answer 219352 by checkley77(12569) on 2010-05-19 18:39:52 (Show Source):
You can put this solution on YOUR website!D=RT
180=(R+20)T
T=180/(R+20)
120=RT
T=120/R
SET THE 2 T EQUATIONS EQUAL.
180/(R+20)=120/R CROSS MULTIPLY.
180R=120(R+20)
180R=120R+2,400
180R-120R=2,400
60R=2,400
R=2,400/60
R=40 mph. for the slower car.
40+20=60 mph. for the faster car.
Proof:
180/60=120/40
3=3 ans. for the travel time.
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Circles/306405: What is the radius if the circumference is:
4x-10pi
(5/2)pi
14pi
(x + y)pi
I have previously completed these problems. However, my answers were deemed incorrect. I would be grateful for assistance. Cheers!
1 solutions
Answer 219336 by checkley77(12569) on 2010-05-19 18:03:05 (Show Source):
You can put this solution on YOUR website!C=2PI*R
4x-10pi
4X-10PI=2PI*R
(4X-10PI)/2=PI*R
2X-5PI=PI*R
R=(2X-5PI)/PI ANS.
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(5/2)pi
5PI/2=2PI*R
R=(5PI/2)/2PI
R=(5PI/2)(1/2PI)
R=5PI/4PI
R=5/4 ANS.
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14pi
14PI=2PI*R
R=14PI/2PI
R=7 ANS.
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(x + y)pi
(X+Y)PI=2PI*R
R=(X+Y)PI/2PI
R=(X+Y)/2 ANS.
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Geometry_Word_Problems/306420: The measure of the vertex angle of an isosceles triangle is three times the measure of the base angle. Find the measure of the vertex angle?
Thanks.
1 solutions
Answer 219332 by checkley77(12569) on 2010-05-19 17:41:34 (Show Source):
You can put this solution on YOUR website!THE VERTEX ANGLE=3X.
THE 2 BASE ANGLES EACH=X.
3X+X+X=180
5X=180
X=180/5
X=36 FOR THE 2 BASE ANGLES.
3*36=108 FOR THE VERTEX ANGLE.
PROOF:
108+36+36=180
180=180
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Roman-numerals/306442: bayside insurance offers two health plans. under plan a, giselle would have to pay the first $60 of her medical bills, plus 25% of the rest. under the plan b, giselle would pay the first $250 , but only 20% of the rest. for what amount of medical bills will plan b save giselle money? assume she has over $350 in bills giselle would save with plan b if she had more than $ in bills.
1 solutions
Answer 219326 by checkley77(12569) on 2010-05-19 17:29:40 (Show Source):
You can put this solution on YOUR website!A=60+.25X
B=250+.20X
60+.25*350=50+$87.50 IS HER PAYMENT.
250+.20*350=250+70=$320 IS HER PAYMENT.
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60+.25X>250+.20X
.25X-.20X>250-60
.05X>190
X>190/.05
X>$3,800 IS THE BREAKEVEN POINT ABOVE WHICH PLAN B IS A BETTER DEAL.
PROOF:
LET X=3,850
60+.25*3,850>250+.20*3,850
60+962,5>250+770
1,022.5>1,020
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