The sum of the ages of a father and son is 48 years. Four years ago, the father was 4 times as old as the son. Let present ages be f and s: f + s = 48 and f - 4 = 4(s - 4). Use substitution to find the son's present age (in years).

Question

Accepted Answer

12. f = 48 - s. Substitute into f - 4 = 4(s - 4): (48 - s) - 4 = 4s - 16, 44 - s = 4s - 16, 60 = 5s, s = 12 (then f = 36). Check: 4 years ago son 8, father 32 = 4 x 8. Correct.

The sum of the ages of a father and son is 48 years.
Four years ago, the father was 4 times as old as the son.
Let present ages be f and s: f + s = 48 and f - 4 = 4(s - 4).
Use substitution to find the son's present age (in years).

Step-by-Step Solution

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More Class 10 Substitution Method practice

The sum of the ages of a father and son is 48 years.Four years ago, the father was 4 times as old as the son.Let present ages be f and s: f + s = 48 and f - 4 = 4(s - 4).Use substitution to find the son's present age (in years).

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 10 Substitution Method practice

The sum of the ages of a father and son is 48 years.
Four years ago, the father was 4 times as old as the son.
Let present ages be f and s: f + s = 48 and f - 4 = 4(s - 4).
Use substitution to find the son's present age (in years).