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percentage/157040: An operation has a 10 percent scrap rate. As a result, 72 pieces per hour are produced. What is the potential increase in labor productivity that could be achieved by eliminating the scrap?
1 solutions
Answer 115793 by checkley77(12569)   on 2008-09-15 10:06:02 (Show Source):
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percentage/157041: An operation has a 10 percent scrap rate. As a result, 72 pieces per hour are produced. What is the potential increase in labor productivity that could be achieved by eliminating the scrap?
1 solutions
Answer 115792 by checkley77(12569) on 2008-09-15 10:05:22 (Show Source):
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percentage/157042: Please explain. A manager checked production records and found that a worker produced 160 units while working 40 hours. In the previous week, the same worker produced 138 units while working 36 hours. Did the worker's productivity increase, decrease, or remain the same? Explain how?
1 solutions
Answer 115791 by checkley77(12569) on 2008-09-15 10:02:45 (Show Source):
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Linear-systems/156924: write a linear equation in standard form, given the following information...
A line through -3,2 and parallel to a line with a slope of -4
1 solutions
Answer 115696 by checkley77(12569) on 2008-09-14 18:24:49 (Show Source):
You can put this solution on YOUR website!2=-4*-3+b
2=12+b
b=2-12
b=-10
Thus the line equation is:
Y=-4X-10
 (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, -4x -10).
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Surface-area/156906: If sides of a square are lengthened by 8 centimeters, the area becomes 144 cm. Find the length of a side of the original square
1 solutions
Answer 115692 by checkley77(12569) on 2008-09-14 18:08:25 (Show Source):
You can put this solution on YOUR website!(x+8)^2=144 taking the sqrt of both sides we get:
x+8=sqrt144
x+8=12
x=12-8
x=4 cm for the original sides of the square.
Proof:
(4+8)^2=144
12^2=144
144=144
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Graphs/156911: Mr.O'Leary is 4 times as old as his son. In 16 years he will be only twice as old. What are theri ages. (Hint: If the son is x years old now, how old will he be in another 16 years?)
1 solutions
Answer 115690 by checkley77(12569) on 2008-09-14 18:00:17 (Show Source):
You can put this solution on YOUR website!4x=x son=x thus mr=4*son=4x
In 16 years they will be:
4x+16=2(x+16)
4x+16=2x+32
4x-2x=32-16
2x=16
x=16/2
x=8 years old for the son.
Dad=4*8=32 years old.
Proof:
4*8+16=2(8+16)
32+16=2*24
48=48
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Equations/156913: Mr.O'Leary is 4 times as old as his son. In 16 years he will be only twice as old. What are their ages. (Hint: If the son is x years old now, how old will be in another 16 years?)
1 solutions
Answer 115689 by checkley77(12569) on 2008-09-14 17:58:12 (Show Source):
You can put this solution on YOUR website!4x=x son=x thus mr=4*son=4x
In 16 years they will be:
4x+16=2(x+16)
4x+16=2x+32
4x-2x=32-16
2x=16
x=16/2
x=8 years old for the son.
Dad=4*8=32 years old.
Proof:
4*8+16=2(8+16)
32+16=2*24
48=48
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Travel_Word_Problems/156837: trains a and b sre traveling in the same direction on parallel tracks. train a is traveling at 40 mile per hour and train b is traveling at 60 miles per hour. train a passes a station at 5:25pm. if train b pass the same station at 5:37pm what time will train b catch up to train a
1 solutions
Answer 115681 by checkley77(12569) on 2008-09-14 16:45:05 (Show Source):
You can put this solution on YOUR website!40t=60(t-.2)
40t=60t-12
40t-60t=-12
-20t=-12
t=-12/-20
t=.6 hours or 36 minutes they will meet.
Proof:
40*.6=60(.6-.2)
24=60*.4
24=24
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Numbers_Word_Problems/156863: At 11:00a.m. Kate left the Clinton toll booth traveling west at 80 km/h. At 12:00p.m. Juan left the toll booth traveling west at 72 km/h. At what time will the two cars be 98 km apart?
This is what I have so far...Kate: 80(x+1)
Juan: 72x
80(x+1)+72x=98
152x=18
x=.118
Not sure what to do after this..thanks.
1 solutions
Answer 115678 by checkley77(12569) on 2008-09-14 16:27:04 (Show Source):
You can put this solution on YOUR website!80(x+1)+72x=98
------------------------------------------
Equation should be 80(t+1)-72t=98
80t+80-72t=98
8t=98-80
8t=18
t=18/8
t=2.25 hours they'll be 98 miles apart.
Proof:
80(2.25+1)-72*2.25=98
80*3.25-162=98
260-162=98
98=98
-----------------------------------------
152x=18
x=.118
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Money_Word_Problems/156867:
3. In 2002, Home Depot’s sales amounted to $58,200,000,000. In 2006, its sales were $90,800,000,000.
a. Write Home Depot’s 2002 sales and 2006 sales in scientific notation.
You can find the percent of growth in Home Depot’s sales from 2002 to 2006, follow these steps:
• Find the increase in sales from 2002 to 2006.
• Find what percent that increase is of the 2002 sales.
b. What was the percent growth in Home Depot’s sales from 2002 to 2006? Do all your work by using scientific notation.
1 solutions
Answer 115676 by checkley77(12569) on 2008-09-14 16:19:16 (Show Source):
You can put this solution on YOUR website!58,200,000,000=5.82 *10^10
90,800,000,000=9.08*10^10
9.08-5.82=3.26*10*^10 is the growth.
3.26/5.82=.56 or 56% increase from 2002
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Quadratic_Equations/156881: 9) Solve. Round results to the nearest thousandth.
7x2 - 6x - .4255 = 0
1 solutions
Answer 115672 by checkley77(12569) on 2008-09-14 16:01:47 (Show Source):
You can put this solution on YOUR website!7x2 - 6x - .4255 = 0
Using the quadratic equation:  WE get;
x=(6+-sqrt[-6^2-4*7*-.4255])/2*7
x=(6+-sqrt[36+11.914])/14
x=(6+-sqrt47.914)/14
x=(6+-6.922)/14
x=12.922/14
x=.923 answer.
x=(6-6.922)/14
x=-.922/14
x=-.066 answer.
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Volume/156887: 19.The exterior dimensions of an empty cooler in the shape of a rectangular prism are 18 inches by 18 inches by 24 inches. For insulation, the top, the bottom and each of the four walls are two inches thick. What is the volume of the empty space inside the cooler?
1 solutions
Answer 115665 by checkley77(12569) on 2008-09-14 15:46:57 (Show Source):
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Radicals/156727: sqrt to the 3rd power, 250x^5y^3 divided by sqrt to the 3rd power, 2x^3
1 solutions
Answer 115562 by checkley77(12569) on 2008-09-13 17:55:00 (Show Source):
You can put this solution on YOUR website!sqrt to the 3rd power, 250x^5y^3 divided by sqrt to the 3rd power, 2x^3
Do you mean: sqrt(250x^5y^3)^3/sqrt(2x^3)^3?
sqrt(250*250*250x^14*xy^9)/sqrt(2*2*2y^9) factoring the 250 & the 8.
cancel out the sqrt(y^9), extract the 250, x^7 & the 2.
250x^7sqrt(250*x)/2sqrt2 divide by 2.
125sqrt(250x)/sqrt2 factor the 250=25810
125sqrt(25*10x)/sqrt2 extract the 5.
625sqrt(10x)/sqrt2
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Polynomials-and-rational-expressions/156720: Please check my answers
Please check my work
add,subtract,multiply or divide the polynomials
3x(-4x^2+5x+14) = -12x^3+15x^2+42x
(7x-5)^2 = 49x^2+25
(3x+4y)(3x-4y) = 9x^2-16y^2
(4x^2-17x-2)divided by (2x+3) =2x+23x-2/2x+3
(2/3x^3-1/2x+1/4)-(2/5x^2-1/3x+1/9) =2/3x^3-1/6x+5/26-2/5x^2
(4x^3+19x^2-7x-14) divided by(3x+4)= 4/3x^2+41/9x
(-7x^2+5xy-2y^2)+(3x^2-5xy-4y^2) = -4x^2-6y^2
(6r^3-8rs+4s^2)-(-5r^3+3rs+s^2) = 11r^2-11rs+2r^2
(8x^2+11xy-17y^2)+(2x^2+4xy-18y^2) = 10x^2+15xy-35y^2
(-4x^2y-2z^2y)-(8x^2y-4z^2y)+(-6x^2y+14xy^2) = -18x^2y=2z^2y+14xy^2
Thank you so much
1 solutions
Answer 115559 by checkley77(12569) on 2008-09-13 17:40:13 (Show Source):
You can put this solution on YOUR website!(2/3 x^3 - 1/2 x + 1/4)-(2/5 x^2 - 1/3 x + 1/9) please do that one again.
OK. I'll try.
2x^3/3-x/2+1/4-2x^2/5+x/3-1/9
2x^3/3-2x^2/5-x/2+x/3-1/9+1/4
2x^3/3-2x^2/5-(3x-2x)/2*3-(-4+9)/9*4
2x^3/3-2x^2/5-x/6-5/36
IF YOU NEED TO COMBINE THE FRACTIONS THEN THE COMMON DENOMINATOR IS 36*5=180:
(60*2x^3-36*2x^2-30*x-5*5)/180
120x^3-72x^2-30x-25)/180
------------------------------------------------------------------------
{used to show the correct values}
3x(-4x^2+5x+14) = -12x^3+15x^2+42x OK.
(7x-5)^2 = 49x^2+25 WRONG
(49x^2{-70x}+25) CORRECT.
(3x+4y)(3x-4y) = 9x^2-16y^2 OK.
(4x^2-17x-2)divided by (2x+3) =2x+23x-2/2x+3 WRONG.
(2x-{11.5) & 32.5/(2x+3)}CORRECT.
(2/3x^3-1/2x+1/4)-(2/5x^2-1/3x+1/9) =2/3x^3-1/6x+5/26-2/5x^2 WRONG.
2x^3/3-2x^2/5-x/2-x/3+1/4+1/9=2x^3/3-2x^2/5-(3x+2x)/6+(9+4)/36
2x^3/3-2x^2/5-{5x/6+13/36} CORRECT.
(4x^3+19x^2-7x-14) divided by(3x+4)= 4/3x^2+41/9x WRONG.
4x^2/3+41x/9-{227/27 & (19 17/27)/(3x+4)} CORRECT.
(-7x^2+5xy-2y^2)+(3x^2-5xy-4y^2) = -4x^2-6y^2 OK.
(6r^3-8rs+4s^2)-(-5r^3+3rs+s^2) = 11r^2-11rs+2r^2 WRONG.
11r^3-11rs+2{s^}2 CORRECT.
(8x^2+11xy-17y^2)+(2x^2+4xy-18y^2) = 10x^2+15xy-35y^2 OK.
(-4x^2y-2z^2y)-(8x^2y-4z^2y)+(-6x^2y+14xy^2) = -18x^2y=2z^2y+14xy^2 WRONG.
-18x^2y{+}2z^2y+14xy^2 CORRECT.
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