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Mathtut answered: 3667 problems
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1 solutions
Answer 124861 by Mathtut(3670)   on 2008-11-24 13:40:21 (Show Source):
You can put this solution on YOUR website!this is a right triangle problem so pathorean theorem states 
c is the hypothenuse and is the distance the car is to the train (50 meters)
:
we will call one of the legs, lets say a, the distance the car is from the crossing (30 meters). So we are looking for b the distance the train is from the crossing
:
:
b^2=1600
:
 the distance the train is from the crossing
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Human-and-algebraic-language/169293: This question is from textbook
Tony has 600 feet of fencing to use in making a yard for her new puppy. The yard she has planned has a length that is 75 feet less than twice the width. What are the dimensions of the yard?
1 solutions
Answer 124853 by Mathtut(3670) on 2008-11-24 11:27:17 (Show Source):
You can put this solution on YOUR website!P=2L+2w: L=2w-75: P=600 plug in P's and L's values into perimeter equation
600=2(2w-75)+2w
600=4w-150+2w
:
6w=750
:
 width
 length
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Miscellaneous_Word_Problems/169306: A company is trying to determine which computer system to install. System A: consists of a central minicomputer costing $100,000 plus desktop terminals costing $800 each. System B: is a network of desktop personal computers that costs $16,000 to install plus $1,200 for each desktop personal computer. How many desktop setups would the company need in order to make the costs of the two systems equal?
trying to solve I ask: how many people are getting a computer? Number of people = x
how do I write out each problem ? 100,000 + 800(x) I am stumped, then 16,000 + 1,200 (x) ?
Your help would be greatly appreciated. I am unable to find a sample in my book .
Thank You
1 solutions
Answer 124849 by Mathtut(3670) on 2008-11-24 11:13:02 (Show Source):
You can put this solution on YOUR website!your on the right track:
:
let A = the number of desktops
:
these two must equal each other in terms of costs so set the two equation = to one another.
:
100000+800A=16000+1200A
:
400A=84000
:
 which is the number of desktops it would take to make these two systems equal
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Age_Word_Problems/169335: A man passed one-sixth of his life in childhood, one twelfth in youth and one seventh in childless marriage. After 5 years of marriage, the man had a child. Alas! Late - born wretched child; after attaining half her father's life, cruel fate overtook her, leaving the man to spend his last 4 years solving math problems. What was the man's final age?
Please give me the representation of that....
thank you very very much for those who answer my question.
1 solutions
Answer 124845 by Mathtut(3670) on 2008-11-24 10:53:10 (Show Source):
You can put this solution on YOUR website!lets call age of this man A
so (1/6)A+(1/12)A+(1/7)A+5+(1/2)A+4=A------->multiply by lcd 84
:
14A+7A+12A+420+42A+336=84A
:
9A=756
:
 mans final age-->he didnt start solving math problems til he was 80...lol
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Percentage-and-ratio-word-problems/169295: This question is from textbook
Susan is planning on investing her $1,600 bonus, putting some in an account earning 6% and the rest in an account earning 8%. How much should she put in each to have a total of $104 interest?
1 solutions
Answer 124821 by Mathtut(3670) on 2008-11-24 00:43:41 (Show Source):
You can put this solution on YOUR website!The amount of money invested at each rate added together will equal the interest earned. call x the amount invested at 6% and 1600-x the amount invested at 8%
:
.06(x)+.08(1600-x)=104
:
.06x+128-.08x=104
:
.02x=24
:
 invested at 6%
 invested at 8%
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Numbers_Word_Problems/169298: The sum of two numbers is 23. The larger number of two numbers is one less than twice the smaller. Find the numbers.
1 solutions
Answer 124820 by Mathtut(3670) on 2008-11-24 00:35:03 (Show Source):
You can put this solution on YOUR website!lets call the numbers a and b(we will call b the larger)
a+b=23
b=2a-1
substitute b's value from 2nd equation into the 1st equation
:
a+(2a-1)=23
:
3a=24
:
 the smaller number
 the larger number
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Sequences-and-series/169216: Don't understand sequences, can anyone help?
Evaluate this sum:
S= 15 + 9 + 27/5 + 81/25 +.......
1 solutions
Answer 124817 by Mathtut(3670) on 2008-11-23 22:06:46 (Show Source):
You can put this solution on YOUR website!ahhhhhhh they tried to be tricky on this one....well it simple enough to see we are working with 3's and 5's and that the numerator term say in 27/5 is  while the denominator is  and the next term 81/25 is numerator is  while the denominator is  , meaning the terms 3 and 5 are increasing by 1 each time. Its the 1st two terms that are the tricky ones but if you back the exponents up on each of the numerator and denominator making 9=  then things begin to make some sense since  . For 15 you would write this as  =15
so now its easy to see the pattern which is  where n is natural numbers starting with 1
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Linear-equations/169222: i need homework help.
i am stuck on linear equations.
how do i figure out if an equation in linear then how do i graph it after that?
like 3/x+4y=10 or 4y-2x=0
1 solutions
Answer 124808 by Mathtut(3670) on 2008-11-23 21:34:16 (Show Source):
You can put this solution on YOUR website!http://www.wtamu.edu/academic/anns/mps/math/mathlab/beg_algebra/beg_alg_tut21_graph.htm
http://www.purplemath.com/modules/graphlin.htm
plot points to graph it....
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Sequences-and-series/169218: Have trouble understanding sequences, can anyone give assistance?
Find ratio, r, the general term, a(base-n), and a(base-11)
2,-6,18,-54,162,...
1 solutions
Answer 124802 by Mathtut(3670) on 2008-11-23 20:50:07 (Show Source):
You can put this solution on YOUR website!t(n) = a[r^(n-1)]
where
t(n) = 'n'th term
a = first term of the sequence
r = common ratio between two successive terms
Here a=2, r=3
hence you get 2,-6,18,-54,162...
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Expressions-with-variables/169229: I know this is a very simple type of equation, but I've forgotten which ones can cancel out and which have to stay.
This is the problem:
(6a)(-4b)
_________
(-2ab)(-3b)
It's multiple choice, so the possible answers are:
A. 4b
B. 4/b
C. -4a
D. -4/a
E. -4/b
Please help!
1 solutions
Answer 124799 by Mathtut(3670) on 2008-11-23 20:19:40 (Show Source):
You can put this solution on YOUR website!just seperate all the terms in there own parentheis and start cancelling
 a's canel 1 b cancels and you end with -4 constant in the numerator and a b in the denominator.
:
you end up with -4/b
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Mixture_Word_Problems/169246: A confectioner has candy costing 55 cents and 75 cents per kilogram. If he wishes to make 1000 kilograms of a mixture and sell it for 60 cents per kilogram, how much of each does he need?
1 solutions
Answer 124789 by Mathtut(3670) on 2008-11-23 19:54:20 (Show Source):
You can put this solution on YOUR website!x+y=1000: eq 1 where x is the amount of 55 cent mixture and y is the amount
of 75 cent mixture
:
.55x+.75y=.6(1000)...eq 2
lets take the y value of eq 1 which is y=1000-x and plug it into eq 2.
:
.55x+.75(1000-x)=600
:
.55x+750-.75x=600
:
.2x=150
 kg of 55 cent candy
 kg of 75 cent candy
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Linear_Algebra/168846: This question is from textbook Prentice Hall algebra2 with trigonometry
Please help me solve this equation:
Number solving Using three equations:
Kristen has a total of 225 on three tests. The sum of the scores on the first and second tests exceeds her third score by 61. her first score exceeds her second by 6. Find the 3 scores.
1 solutions
Answer 124511 by Mathtut(3670) on 2008-11-20 22:19:46 (Show Source):
You can put this solution on YOUR website!lets call the scores on her 3 tests a,b,and c
a+b+c=225...eq 1
a+b=c+61....eq 2
a=b+6.......eq 3
lets plug a's value from eq 3 into b+6+b=c+61----solve for c in terms of b
c=2b-55.
now we take this value of c and a's value from eq 3 and plug them into eq 1
:
(b+6)+b+2b-55=225
4b=164
:
 score
 score
 score
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Equations/168851: complete each ordered pair so that it satisfies the given equation:
y=2x+5:(8,?),(-1,?),(?,-1)
I figured out 8,21 and -1,3, but I am thrown on the last pair
1 solutions
Answer 124506 by Mathtut(3670) on 2008-11-20 22:05:52 (Show Source):
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Linear-systems/168849: This question is from textbook Prentice Hall Algebra 2 with trigonometry
Please help me solve this equation:
using a system of two equations.
The sum of a certain number and a second number is -42. The first number minus the second is 52. Find the numbers.
1 solutions
Answer 124505 by Mathtut(3670) on 2008-11-20 22:00:30 (Show Source):
You can put this solution on YOUR website!lets call the numbers a and b
:
a+b=-42...eq 1
a-b=52....eq 2
using the elimination method to solve means we try to eliminate one of the variables and we can do that just by adding the 2 equation together(the b terms cancel out.
:
we end up with 2a=10---> divide by 2 and 
:
to find b just plug a's value into either equation
:
5-b=52--->subtract 5 from each side and divide by -1 
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