Question 1157205
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Using logical reasoning and some simple mental arithmetic, instead of formal algebra (if a formal algebraic solution is not required!)...<br>
The boy is 1/5 of his father's age --> the boy is 1/6 of the SUM of their ages; the father is 5/6 of the SUM.<br>
The sum of their ages 3 years from now is 72 --> the sum of their ages now is 72-2*3 = 66.<br>
The son's age is 1/6 of 66, which is 11; the father is 5/6 of 66, which is 55.<br>
ANSWERS: 11 and 55<br>