SOLUTION: Kindly answer these problems please because i am still quite confused in answering these problems and please apply system of linear equations. 1) Working together, Tom and Jer

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Question 412922: Kindly answer these problems please because i am still quite confused in answering these problems and please apply system of linear equations.
1) Working together, Tom and Jerry cleaned the swimming pool in 6 hrs. If both of them worked together for the 1st 3 hrs., and Jerry stopped for an errand it would require Tom 4 hrs. to finish cleaning the pool. How long would it take Jerry to clean the pool alone? How long would it take Tom?

Thank you in advance! Hoping for your immediate reply.

Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
1) Working together, Tom and Jerry cleaned the swimming pool in 6 hrs.
If both of them worked together for the 1st 3 hrs, and Jerry stopped for an
errand it would require Tom 4 hrs. to finish cleaning the pool.
How long would it take Jerry to clean the pool alone?
How long would it take Tom?
:
Let t = time required by Tom alone
Let j = time required by Jerry alone
:
Let the completed job = 1 (a clean pool)
:
Write an equation for each statement:
:
" Working together, Tom and Jerry cleaned the swimming pool in 6 hrs."
+ = 1
:
"If both of them worked together for the 1st 3 hrs, and Jerry stopped, it would
require Tom 4 hrs. to finish cleaning the pool." (Tom works a total of 7 hrs)
+ = 1
multiply the above equation by 2, subtract the 1st equation from it:
+ = 2
+ = 1
-----------------------subtraction eliminates j find t
= 1
Multiply both sides by t and you have
t = 8 hrs, Tom working alone
:
Find j using the 1st equation
+ = 1
multiply by 8j
6j + 8(6) = 8j
48 = 8j - 6j
48 = 2j
j =
j = 24 hrs, Jerry working alone; (not much help, perhaps he only had one arm)
:
:
Confirm these solutions in the 2nd equation
+ =
+ = 1;