Question

A man is six times as old as his son. In 9 years he will be three times as old as his son. How old are they now?​

Answer 1

f, s={36,6} is your answer.

Explanation:

PREMISES

6s+9=3(s+9)

ASSUMPTIONS/SUFFICIENT CONDITION(S)

Let the son's current age s=s

Let the father's current age f=6s

CALCULATIONS

6s+9=3(s+9)

6s+9=3s+27

6s-3s+(9–9)=3s-3s+(27–9)

3s+0=0+18

3s=18

3s/3=18/3

s=

6

and,

if s=6, then

6s=

f=

36

PROOF

If f,s=36, 6, then the equations

6s+9=3(s+9)

6(6)+9=3(6+9)

36+9=3(15) and

45=45 establish the roots (zeros) f, s=36,6 of the mathematical statement 6s+9=3(s+9)