Let us assume the age of Robert now as 'x' years.

Statement 1
Age now = x, age after five years = x+5. Given:
x*(x+5) = 24. Only positive value of 'x' that satisfies this is '3'. (3*8 = 24).
This means Robert's age now is '3 years. Sufficient.

Statement 2
Age now = x, age after six years = x+6. Given:
x+6 = 3*x or 2x = 6 or x=3.
This means Robert's age now is '3' years. Sufficient.

Hence D answer

Let N = Robert's age NOW

Target question: What is the value of N?

Statement 1: The product of his age now and his age five years from now is 24.
If N = Robert's age NOW...
then N+5 = Robert's age in 5 years

We can write: N(N + 5) = 24
Expand: N² + 5N = 24
Rewrite as: N² + 5N - 24 = 0
Factor: (N + 8)(N - 3) = 0

So, EITHER N = -8 OR N = 3
Since Robert's age cannot be NEGATIVE, we can conclude with certainty that N = 3
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: Six years from now he will be three times as old as he is now.
If N = Robert's age NOW...
then N+6 = Robert's age in 6 years

We can write: N + 6 = 3N
Solve: N = 3
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Answer: D

Cheers,
Brent
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