Subtract 5 (Cameron) and 2 (Karlee) from 49.
Why: Denise's age is basically the basic number. Karlee would be 2 years older, so subtract 2 from 49. You get 47. Cameron is 5 years older than Denise, so subtract 5. You get 42 and divide that by 3 since there are 3 people.
49 - 7 = 42
42 divide by 3 = 14
Check:
14 + 5 = 19
14 + 2 = 16
14 + 0 = 14
19 + 16 + 14 = 49
19 (Cameron) - 16 (Karlee) = 3 years older
16 (Karlee) - 14 (Denise) = 2 years older
19 (Cameron) - 14 (Denise) = 5 years older
Hopes this helps!