<PRE><B>Question 1146957</B>
let m be the age of the man and s be the age of his son, then
:
1)  m - 4 = 6 * (s - 4)
:
2)  m + 5 = 3 * (s + 5)
:
solve both equations for m and set them equal to each other
:
6 * (s - 4) + 4 = 3 * (s + 5) - 5
:
6s - 24 + 4 = 3s + 15 - 5
:
6s - 20 = 3s + 10
:
3s = 30
:
s = 10
:
substitute for s in equation 2 (Note we could have chosen 1 also)
:
m + 5 = 3 * (10 + 5)
:
m = 40
:
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The man is 40 and his son is 10
:
check the answers
:
40 - 4 = 6 * (10 - 4)
:
36 = 36
:
40 + 5 = 3 * (10 + 5)
:
45 = 45
:
answers check
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