Adam's age is a multiple of 9 this year.
His age next year will be multiple of 7.
Adam's age is between 20 and 30.
- What is Adam's age this year?
- What was Adam's age 6 years ago?
- What is Adam's age 3 years later?
Multiple of 9: 9, 18, 27
Multiple of 9 (+1): 10, 19, 28
Multiple of 7: 7, 14, 21, 28
28 appears in both the multiples of 9 (+1) and the multiples of 7.
(a) Adam's age this year = 27
(b) Adam's age 6 years ago = 27 - 6 = 21
(c) Adam's age 3 years later = 27 + 3 = 30
Answer(s): (a) 27; (b) 21; (c) 30