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checkley77 answered: 12560 problems
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For one night, the recipts were $85 and 100 people paid. How many people were adults? 1 solutions
Answer 123754 by checkley77(12569) on 2008-11-16 16:38:27 (Show Source):
You can put this solution on YOUR website!1.25X+.75(100-X)=85
1.25X+75-.75X=85
.5X=85-75
.5X=10
X=10/.5
X=20 ADULT TICKETS WERE SOLD.
PROOF:
1.25*20+.75(100-20)=85
25+.75*80=85
25+60=85
85=85
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Numbers_Word_Problems/167909: Find the number of two-digit positive integers whose digits total 7. I know the answer is 7 (16, 25, 34, 43, 52, 61, 70) but my teacher wants me to show it in an algebraic formula. How do I do that? This question is not from a textbook. 1 solutions
Answer 123753 by checkley77(12569) on 2008-11-16 16:35:41 (Show Source):
You can put this solution on YOUR website!X+Y=7
MAKE UP A TABLE WITH X=0,1,2,3,4,5,6 & 7 AND SOLVE FOR Y.
0+Y=7
Y=7 OR 07
1+Y=7
Y=7-1
Y=6 OR 16
2=Y=7
Y=7-2
Y=5 OR 25
3=Y=7
Y=7-3
Y=4 OR 34
5+Y=7
Y=7-5
Y=2 OR 52
6+Y=7
Y=7-6
Y=1 OR 61
7+Y=7
Y=7-7
Y=0 OR 70
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Finance/167896: can someone help please:
Find the present value of the future amount. Assume 365 days in a year. Round to the nearest cent.
$15,000 for 110 days; money earns 8% 1 solutions
Answer 123750 by checkley77(12569) on 2008-11-16 16:19:16 (Show Source):
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Rational-functions/167898: I need to solve for x.
4x(x-2)-5x(x-1)=2
I have already taken the steps to make the problem
4x^2-8x-5x^2-5x=2, but that is all I have. I have been trying by "substitution", but have not found the answer. Please help me solve for x.
Thank you,
Rachel 1 solutions
Answer 123748 by checkley77(12569) on 2008-11-16 16:12:50 (Show Source):
You can put this solution on YOUR website!4x(x-2)-5x(x-1)=2
4X^2-8X-5X^2+5X-2=0
-X^2-3X-2=0
X^2+3X+2=0
(X+2)(X+1)=0
X+2=0
X=-2 ANS.
X+1=0
X=-1 ANS.
PROOFS:
4*-2(-2-2)-5*-2(-2-1)=2
-8*-4+10*-3=2
32-30=2
2=2
4*-1(-1-2)-5*-1(-1-1)=2
-4*-3+5*-2=2
12-10=2
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Equations/167901: I have to write an inequality that demonstrates that I wish to spend no less than $6000 and no more than #10000. How do I go about this?
1 solutions
Answer 123747 by checkley77(12569) on 2008-11-16 16:10:39 (Show Source):
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Rational-functions/167899: I am working with my school website on My Math Lab and this is a question asked. I need to solve for x.
4x(x-2)-5x(x-1)=2
I have already taken the steps to make the problem
4x^2-8x-5x^2-5x=2, but that is all I have. I have been trying by "substitution", but have not found the answer. Please help me solve for x.
Thank you,
Rachel 1 solutions
Answer 123746 by checkley77(12569) on 2008-11-16 16:09:02 (Show Source):
You can put this solution on YOUR website!4x(x-2)-5x(x-1)=2
4X^2-8X-5X^2+5X-2=0
-X^2-3X-2=0
X^2+3X+2=0
(X+2)(X+1)=0
X+2=0
X=-2 ANS.
X+1=0
X=-1 ANS.
PROOFS:
4*-2(-2-2)-5*-2(-2-1)=2
-8*-4+10*-3=2
32-30=2
2=2
4*-1(-1-2)-5*-1(-1-1)=2
-4*-3+5*-2=2
12-10=2
2=2
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Linear_Algebra/167817: Solve each system by the addition method.
x + y = 7
X y = 9
x y = 12
2x + y = 3
2x y = -5
3x + 2y = 3
3x + 4y = -5
5x + 6y = -7 1 solutions
Answer 123722 by checkley77(12569) on 2008-11-16 09:54:40 (Show Source):
You can put this solution on YOUR website!x+y=7
xy=9 add
-------------
2x=16
x=16/2
x=8 ans.
8+y=7
y=7-8
y=-1 ans.
*************************
xy=12
2x+y=3 add
-------------------
3x=15
x=15/3
x=5 ans.
5-y=12
-y=12-5
-y=7
y=-7 ans.
***********************************
2xy=-5 multiply this equation by 2 & add.
3x+2y=3
4x-2y=-10
-----------
7x=-7
x=-7/7
x=-1 ans.
2*-1-y=-5
-2-y=-5
-y=-5+2
-y=-3
y=3 ans.
*************************
3x+4y=-5 multiply by 5
5x+6y=-7 multiply by -3 & add.
15x+20y=-25
-15x-18y=21
------------------
2y=-4
y=-4/2
y=-2 ans.
3x+4*-2=-5
3x-8=-5
3x=-5+8
3x=3
x=3/3
x=1 ans.
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Square-cubic-other-roots/167824: Find all real or imaginary solutions.
Sqrt(2x^2+x-12)=x 1 solutions
Answer 123719 by checkley77(12569) on 2008-11-16 09:44:22 (Show Source):
You can put this solution on YOUR website!Sqrt(2x^2+x-12)=x squaring both sides we get:
2x^2+x-12=x^2
2x^2-x^2+x-12=0
x^2+x-12=0
(x+4)(x-3)
x+4=0
x=-4 ans.
x-3
x=3 ans.
Proofs:
sqrt(2*-4^2+(-4)-12=-4
sqrt(2*16-4-12)=-4
sqrt(32-16)=-4
sqrt16=-4
-4=-4
sqrt(2*3^2+3-12)=3
sqrt(2*9+3-12)=3
sqrt(18+3-12)=3
sqrt9=3
3=3
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Numeric_Fractions/167822: Mother spent 1/2 of her money in the first store. She spent 2/3 of her money in the second store. She has $25 left. How much money does she have first? 1 solutions
Answer 123712 by checkley77(12569) on 2008-11-16 09:05:34 (Show Source):
You can put this solution on YOUR website!x=25+2/3*1/2x+1/2x
x=25+2x/6+x/2
x=25+(2x+3x)/6
x=25+5x/6
x-5x/6=25
x/6=25
x=25*6
x=$150 initial amount Mother had.
Proof:
150=25+2/3*150/2+150/2
150=25+300/6+150/2
150=25+50+75
150=150
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Linear_Equations_And_Systems_Word_Problems/167760: john has retired and needs $ 6000 per annum to live. he has $50000 to invest and can invest in bonds at 15 % annual interest or in bank certificates at an annual rate of 7 % .how much money should he invest in each type of investment to get a income of 6000 $ per annum? what if he determines he actually requires an income of 7000 per year 1 solutions
Answer 123676 by checkley77(12569) on 2008-11-15 21:48:35 (Show Source):
You can put this solution on YOUR website!.15x+.07(50,000-x)=6000
.15x+3,500-.07x=6,000
.08x=6,000-3,500
.08x=2,500
x=2,500/.08
x=$31.250 needs to be invested @ 15%
50,000-31,250=18,750 invested @ 7%
-------------------------------------
.15x+.07(50,000-x)=7000
.15x+3,500-.07x=7,000
.08x=7,000-3,500
.08x=3,500
x=3,500/.08
x=43,750 amount invested @ 15%
50,000-43,750=6,250 invested @ 7%
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Miscellaneous_Word_Problems/167771: P dollars is invested at annual interest rate r for 1 year. If the interest is compounded semiannually, then the polynomial p(1+r/2)^2
represents the value of the investment after 1 year. Rewrite this expression
without parentheses. Evaluate the polynomial if P = $200 and r =10%.
I am so confused can someone please help me? Thank you 1 solutions
Answer 123673 by checkley77(12569) on 2008-11-15 21:40:19 (Show Source):
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Travel_Word_Problems/167772: Two cars that are 375 miles apart and whose speeds differ by 5 miles per hour,
are moving toward each other. They will meet in hours. What is the speed of each car?
1 solutions
Answer 123671 by checkley77(12569) on 2008-11-15 21:37:04 (Show Source):
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Rectangles/167691: Find the lenghth of a rectangle when the width is 2 inches shorter and the perimeter is 80. Set up the equation for the perimeter involving only (L)
and then sove the equation for the length and the width. 1 solutions
Answer 123579 by checkley77(12569) on 2008-11-15 08:53:37 (Show Source):
You can put this solution on YOUR website!W=L-2
2L+2W=80
2L+2(L-2)=80
2L+2L-4=80
4L=80+4
4L=84
L=84/4
L=21 ANSWER FOR THE LENGTH.
W=21-2
W=19 ANSWER FOR THE WIDTH.
PROOF:
2*21+2*19=80
42+38=80
80=80
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Exponential-and-logarithmic-functions/167592: I have a word problem that I need help with. I must show my work.
1. In a certain area, the sale price of new single-family homes has increased 4.1% per year since 1992. If a house was purchased in this area in 1992 for $75,000 and the growth continues, what will be sale price in 2006? Use y=a(1+r)^t and round to the nearest cent.
Thanks 1 solutions
Answer 123556 by checkley77(12569) on 2008-11-14 20:30:20 (Show Source):
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Mixture_Word_Problems/167573: 40 liters of pure syrup costs $18. per liter, mixed w/ imitation syrup that cost $8.50 per liter. How much imitation is needed to make a mixture costing $11.00 per liter? 1 solutions
Answer 123474 by checkley77(12569) on 2008-11-14 10:06:31 (Show Source):
You can put this solution on YOUR website!40*18+8.50x=11(40+x)
720+8.50x=440+11x
8.5x-11x=440-720
-2.50x=-280
x=-280/-2.50
x=112 liters of $8.50 imitation syrup is used.
Proof:
40*18+8.50*112=11(40+112)
720+952=11*152
1,672=1,672
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Mixture_Word_Problems/167575: walnuts that cost $4.05 per kilogram were mixed w/ cashews that cost $7.25 per kilogram. How many kilograms of each were used to make a 50 kg. mixture that costs $6.25 per kilogram.(round to nearest 10th). 1 solutions
Answer 123472 by checkley77(12569) on 2008-11-14 10:00:40 (Show Source):
You can put this solution on YOUR website!7.25x+4.05(50-x)=6.25*50
7.25x+202.5-4.05x=312.50
3.2x=312.50-202.50
3.2x=110
x=110/3.2
x=34.38 kg. of cashews are used.
50-34.38=15.62 kg. of walnuts are used.
Proof:
7.25*34.38+4.05*15.62=312.50
249.26+63.26=312.50
-------------------------------------------------
Rounding to thew nearest pound would be 34 & 16.
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Mixture_Word_Problems/167576: walnuts that cost $4.05 per kilogram were mixed w/ cashews that cost $7.25 per kilogram. How many kilograms of each were used to make a 50 kg. mixture that costs $6.25 per kilogram.(round to nearest 10th). 1 solutions
Answer 123469 by checkley77(12569) on 2008-11-14 09:53:08 (Show Source):
You can put this solution on YOUR website!7.25x+4.05(50-x)=6.25*50
7.25x+202.5-4.05x=312.50
3.2x=312.50-202.50
3.2x=110
x=110/3.2
x=34.38 kg. of cashews are used.
50-34.38=15.62 kg. of walnuts are used.
Proof:
7.25*34.38+4.05*15.62=312.50
249.26+63.26=312.50
312.52~312.50
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