Question

$A$'s age is twice as $B$'s age. $4$ years ago, $A$ was three times as old as $B$. Find their present ages.

• A. $30$ years and $15$ years
• B. $20$ years and $10$ years
• C. $10$ years and $5$ years
• D. $16$ years and $8$ years

Answer 1

Answer: (D)

$16$ years and $8$ years

$Letthenumbersbexandy.x=2y;x-4=3(y-4);Substitutingthevalueinthe2ndequation:2y-4=3(y-4);Therefore:y=8x=16$