SOLUTION: Bob is 5 times the age of his daughter Jane. In 5 years time, Bob will be 3 times Jane's age. How old are they now?

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Question 466523: Bob is 5 times the age of his daughter Jane. In 5 years time, Bob will be 3 times Jane's age. How old are they now?
Found 2 solutions by Earlsdon, MARIO OWHOLO:
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Let B = Bob's present age and J = his daughter Jane's present age.
1) B+=+5J "Bob is 5 times the age of his daughter Jane."
2) B%2B5+=+3%28J%2B5%29 "In 5 year's time, Bob will be 3 times Jane's age."
Into equation 2), substitute B+=+5J from equation 1) and solve for J.
3) %285J%29%2B5+=+3%28J%2B5%29 Simplify this.
4) 5J%2B5+=+3J%2B15 Subtract 3J from both sides.
5) 2J%2B5+=+15 Subtract 5 from both sides.
6) 2J+=+10 Divide both sides by 2
7) highlight%28J+=+5%29 Now substitute this value of J into equation 1) to find the value of B.
8) B+=+5%285%29
9) highlight_green%28B+=+25%29
Bob's present age is 25 and his daughter Jane's present age is 5.

Answer by MARIO OWHOLO(4) About Me  (Show Source):
You can put this solution on YOUR website!
Let bob`s age be =b
Nd janes age = j
; b=5*j---equation 1
In 5 yrs time bob will be 3 times janes age
B+5=3(j+5)----equation 2
5j+5=3j+15
2j=10
J=5
Where b=5*5
B=25
Bob is 25yrs old
Also jane is 5yrs old