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Rational-functions/193405: saturn is about 2.87x10^12m from the sun. light travels at approximately 3x10^8 m/s. how long does it take for the suns light to reach saturn? give your answer in seconds and to the nearest minute.
1 solutions
Answer 145201 by Mathtut(3670)   on 2009-04-27 18:05:50 (Show Source):
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Miscellaneous_Word_Problems/193385: A discount store sold plastic cups for $3.50 each and ceramic cups for $4.00 each. If 400 cups were sold for a total of $1,458, how many cups of each type were sold? What was the dollar value of each type of cup sold?
1 solutions
Answer 145197 by Mathtut(3670) on 2009-04-27 17:52:19 (Show Source):
You can put this solution on YOUR website!let x and y be the number of of plasic and ceramic cups sold respectively
:
x+y=400............eq 1
3.5x+4y=1458.......eq 2
:
rewrite eq 1 to x=400-y and plug this value into eq 2
:
3.5(400-y)+4y=1458
:
1400-3.5y+4y=1458
:
.5y=58
:
y=116 ceramic cups
:
x=400-116=284 plastic cups
:
dollar value of plasic cups is 284(3.5)=$994
dollar value of ceramic cups is 116(4)=$464
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Evaluation_Word_Problems/193393: ``Before, solving the problem, I just want to give you the heads up. It's
Systems of Equation: Application. I can't find the specific title to relate
with my story problems. My chapter in the book is Chapter Eight, Solving Systems by Substiution, Additional. Hope it helps!
*The Perimeter of a rectangle is 42 inches. If the length is doubled and the width is tripled, the perimeter becomes 102 inches. Find the length and width of the original rectangle.*
1 solutions
Answer 145196 by Mathtut(3670) on 2009-04-27 17:44:35 (Show Source):
You can put this solution on YOUR website!42=2L+2W--->2L=42-2W.....eq 1
:
102=2(2L)+3(2W)......eq 2
:
take 2L's value from eq 1 and plug it into eq 2
:
102=2(42-2W)+6W
:
102=84-4W+6W
:
18=2W
:
W=9 in
:
L=(42-2(9))/2=24/2=12 in
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Systems-of-equations/193395: ``Before, solving the problem, I just want to give you the heads up. It's
Systems of Equation: Application. I can't find the specific title to relate
with my story problems. My chapter in the book is Chapter Eight, Solving Systems by Substiution, Additional. Hope it helps!
*Two families attend the town's ice cream social every summer. This year one family piad $9.75 for 3 adult tickets and 5 children's tickets. The other family paid $10.75 for 5 adult tickets and 1 child's ticket. Find the price of a child's ticket.*
1 solutions
Answer 145195 by Mathtut(3670) on 2009-04-27 17:38:44 (Show Source):
You can put this solution on YOUR website!let c and a be the prices childrens and adult tickets respectively
:
5c+3a=9.75............eq 1
1c+5a=10.75...........eq 2
:
rewrite eq 2 to c=10.75-5a and plug this value into eq 1
:
5(10.75-5a)+3a=9.75
:
53.75-25a+3a=9.75
:
-22a=-44
:
a=$2
:
c=10.75-5(2)=$.75
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Systems-of-equations/193399: ``Before, solving the problem, I just want to give you the heads up. It's
Systems of Equation: Application. I can't find the specific title to relate
with my story problems. My chapter in the book is Chapter Eight, Solving Systems by Substiution, Additional. Hope it helps!
*Angles A and B are complementary. Angle B is 18 greater than angle A. Find the measures of the two angles.*
1 solutions
Answer 145193 by Mathtut(3670) on 2009-04-27 17:34:01 (Show Source):
You can put this solution on YOUR website!since A and B are complementary
:
A+B=90.......eq 1
B=A+18.......eq 2
:
take B's value of A+18 from eq 2 and plug it into eq 1
:
A+A+18=90
:
2A=72
:
A=36 degrees
:
B=A+18=36+18=54 degrees
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Systems-of-equations/193396: ``Before, solving the problem, I just want to give you the heads up. It's
Systems of Equation: Application. I can't find the specific title to relate
with my story problems. My chapter in the book is Chapter Eight, Solving Systems by Substiution, Additional. Hope it helps!
*Roberto decided to invest 20,000 in two accounts. One fo the accounts pays 5% interest and the other pays 8% interest. The interest he earned in one year was $1210. How much did he have invested in each account?*
1 solutions
Answer 145192 by Mathtut(3670) on 2009-04-27 17:31:22 (Show Source):
You can put this solution on YOUR website!let x and y be the amounts invested at 5 and 8% respectively
:
x+y=20000...............eq 1
.05x+.08y=1210..........eq 2
:
rewrite eq 1 to x=20000-y and plug this into eq 2
:
.05(20000-y)+.08y=1210
:
1000-.05y+.08y=1210
:
.03y=210
:
y=7000 dollars invested at 8%
:
x=20000-y=20000-7000=13000 invested at 5%
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Equations/193394: I have a problem solving this compound interest question.
Question : If 7000 dollars is invested in a bank account at an interest rate of 9 per cent per year, find the amount in the bank after 12 years if interest is compounded annually ?
Now, I have used the compound interest formula A=P(1+(r/n))^nt , and I get 7000. Could someone please help me and see what I am doing wrong in my caluclations? Thanks.
1 solutions
Answer 145190 by Mathtut(3670) on 2009-04-27 17:24:49 (Show Source):
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Miscellaneous_Word_Problems/193253: To determine the number of deer in a game preserve, a conservationist catches 465 deer, tags them, and lets them loose. Later, 676 deer are caught; 169 of them are tagged. How many deer are in the preserve?
1 solutions
Answer 145145 by Mathtut(3670) on 2009-04-27 13:19:24 (Show Source):
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Quadratic_Equations/193345: This question is from textbook
I have a problem that states to ADD THE PROPER CONSTANT TO EACH BINOMIAL SO THAT THE RESULTING TRINOMIAL IS A PERFECT SQUARE TRINOMIAL. THEN FACTOR EACH TRINOMIAL.
x^2-18x+____
How would you solve this?
any help would be greatly appreciated!!
1 solutions
Answer 145141 by Mathtut(3670) on 2009-04-27 13:01:29 (Show Source):
You can put this solution on YOUR website!the constant is always 1/2 of the x terms coefficient squared
:
so in this case the coefficient is -18. divide 18 by 2 and you arrive at -9. The square of -9 equals 81
:
 ---> 
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Probability-and-statistics/193299: Assume that 'x' is a number chosen at random from the sets of integers between 1 and 15 inclusive, what is the probability that 'x' is a:
i) Single digit number
ii) Multiple of 5 or 7
iii) Complete square.
1 solutions
Answer 145139 by Mathtut(3670) on 2009-04-27 12:56:47 (Show Source):
You can put this solution on YOUR website!i) 9 possibles 1-9.... 9/15=3/5
:
ii)5,10,15 7,14....so 5 possibles 5/15=1/3
:
iii)if we are talking about a perfect square we would have 3 possibles 1,4,9...so 3/15=1/5
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Probability-and-statistics/193298: 3) An integer is chosen at random from the first 50bdigits. What is the probability that it is divisible by 6 or 8.
4) An integer is chosen at random from the first 100 positive integers. Find the probability that it is divisible by
i) 8 and 12.
ii) 16 and 20.
1 solutions
Answer 145138 by Mathtut(3670) on 2009-04-27 12:45:59 (Show Source):
You can put this solution on YOUR website!3) there are only 2 numbers that work 24 and 48 so 2/50=1/25
:
4)
i)only 4 numbers work 24,48,72, and 96 so 4/100=1/25
ii)only 1 number works 80.....so 1/100
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Linear-systems/193336: Diane has $1.70 in dimes and nickels. She has a total of 22 coins. How many of each kind does she have?
Nickels
Dimes
1 solutions
Answer 145137 by Mathtut(3670) on 2009-04-27 12:36:47 (Show Source):
You can put this solution on YOUR website!let d and n be the number of dimes and nickels respectively
:
d+n=22..........eq 1
.1d+.05n=1.70...eq 2
:
rewrite eq 1 to d=22-n and plug this value into eq 2
:
.1(22-n)+.05n=1.7
:
2.2-.1n-+.05n=1.7
:
-.05n=-.5
:
n=10 nickels
:
d=22-n=22-10=12 dimes
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Probability-and-statistics/193296: 1) Two cards are drawn at random from a well shuffled pack of 52 cards. Find the probability that:
i) One is king and other is Queen.
ii) Both are of the same colour.
iii) Both are of the different colour.
1 solutions
Answer 145136 by Mathtut(3670) on 2009-04-27 12:32:58 (Show Source):
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Linear-systems/193338: PROBLEM:
A chemist needs 900 millileters of a 40% acid solution for a chemistry experiments. The chemist combines x milliliters of a 20% acid solution and y milliliters of a 70% acid solution to make 40% acid solution.
a. write a linear system that repesents the situation
1 solutions
Answer 145134 by Mathtut(3670) on 2009-04-27 12:27:14 (Show Source):
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Linear-systems/193320: x=1/2y+3
2x-y=6
please help solve these linear equations by using substitution.
1 solutions
Answer 145128 by Mathtut(3670) on 2009-04-27 11:12:52 (Show Source):
You can put this solution on YOUR website!x=1/2y+3........eq 1
2x-y=6..........eq 2
:
take x's value from eq 1 and substitute it into eq 2
:
2((1/2)y+3)-y=6
:
y+6-y=6
:
0=0
:
rewrite eq 2--->-y=-2x+6--->y=2x-6
rewrite eq 1--->y=2x-6
:
these are the same lines(same slope) and same y intercepts therefore there are infinite solutions
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Quadratic-relations-and-conic-sections/193324: ellipse in standard form:
(1/6)(x+2)^2 + (1/9)(y-5)^2= 1
find the center,
foci,
length of the major axis,
and the distance between the two foci
may you please help me find these?
thank you!
1 solutions
Answer 145124 by Mathtut(3670) on 2009-04-27 10:46:35 (Show Source):
You can put this solution on YOUR website!center is at (-2,5)
:
foci c 
:
c= 
:
foci are at (-2,5+sqrt(15)) and (-2, 5-sqrt(15))
:
length of major axis is 2a...a=3 so 2a= 2(3)=6units
:
distance between foci is 
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Inequalities/193316: A coffee shop decides to blend a coffee that sells for $12 per pound with a coffee that sells for $9 per pound to produce a blend that will sell for $10 per pound. How much of each should be used to yield 20 pounds of the new blend?
1 solutions
Answer 145120 by Mathtut(3670) on 2009-04-27 10:08:55 (Show Source):
You can put this solution on YOUR website!let x and y be the amount of 12 and 9 dollar coffee respectively
:
x+y=20...........eq 1
12x+9y=10(20)....eq 2
:
rewrite eq 1 to x=12-y and plug it into eq 2
:
12(20-y)+9y=200
:
240-12y+9y=200
:
-3y=-40
:
y=13.33 pounds of 9 dollar coffee
:
x=20-13.33=6.67 pounds of 12 dollar coffee
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test/193312: In Tiana's monthly budget, she set aside $685 for housing and $265 less than that for food. How much did she budget for food? Do I just subtract 265 from 685?
1 solutions
Answer 145119 by Mathtut(3670) on 2009-04-27 09:59:47 (Show Source):
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Inequalities/193317: Printer A can print a report in 3 hours. Printer B can print the same report in 4 hours. How long would it take both printers, working together, to print the report?
1 solutions
Answer 145117 by Mathtut(3670) on 2009-04-27 09:58:02 (Show Source):
You can put this solution on YOUR website!printer 1 can do 1/3 of the report per hour
printer 2 can do 1/4 of the report per hour
:
together:
:
(1/4+1/3)t=1
:
(3/12+4/12)t=1
:
(7/12)t=1
:
t=12/7 of an hour for both
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Finance/193016: This question is from textbook Practical Business Math Procedures
Fuel inventories were lower than last year according to the San Francisco Chronicle dated February 24, 2007. This year there are 38.6 million barrels of inventory, a 9.72 percent drop.
(a) What was the amount of inventory last year to nearest tenth?
_____million
(b) What was the amount of the decrease?
_____million
1 solutions
Answer 145023 by Mathtut(3670) on 2009-04-26 15:09:38 (Show Source):
You can put this solution on YOUR website!let x be the amount of inventory last year
:
x-.0972x=38.6 million
:
.9028x=38.6
:
x=42.76 or 42.8 million to the nearest tenth
:
the decrease is 42.8-38.6=4.2 million
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Miscellaneous_Word_Problems/193182: Can someone help me please? Word problems are the worst!
A disc jockey plays 12 commercial spots during 1 hr. of radio show. Each commercial is either 30 or 60 sec. long. If the total commercial time in one hr. is 8 min. how many 30 sec. commercials were played that hr.? How many 60 sec.?
Thanks a lot
1 solutions
Answer 145019 by Mathtut(3670) on 2009-04-26 14:49:27 (Show Source):
You can put this solution on YOUR website!perhaps this will help......first step is to search what the problem is asking for
This problem wants to know how many 30 sec and 60 sec commercials there are. Now label the unknowns. Lets call the 30 and 60 sec spots a and b respectively
:
Now try to come up with 2 equations since we have 2 unknowns
:
we are told that there are 12 commercial spots so
:
a+b=12.............eq 1
we know that the total time for commercials is 8 minutes
We must make sure both of these are in the same unit....commercials are in seconds so lets convert to minutes before we write the equation..30 sec =1/2 min and 60 sec =1 minute
:
(1/2)a+b=8.......eq 2
:
rewrite eq 1 to a=12-b and plug this into eq 2
:
(1/2)(12-b)+b=8
:
6-(1/2)b+b=8
:
(1/2)b=2
:
b=4 (60 second spots)
:
a=12-b=12-4=8 (30 second spots)
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Graphs/193159: Hello.
I'm needing some help with the following problem and checking my answers.
f(x) = -(x+1)^2 + 3
thanks!
1 solutions
Answer 145017 by Mathtut(3670) on 2009-04-26 14:22:06 (Show Source):
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