Adam's age is a multiple of 10 this year.
His age 2 years ago was a multiple of 9.
- What is Adam's age this year?
- What was Adam's age 2 years ago?
- What is Adam's age 10 years later?
Multiple of 10: 10, 20
Multiple of 10 (-2): 8, 18
Multiple of 9: 9, 18
18 appears in both the multiples of 10 (-2) and the multiples of 9.
Adam's age 2 years ago = 18
(a) Adam's age this year = 20
(b) Adam's age 2 year ago = 20 - 2 = 18
(c) Adam's age 10 years later = 20 + 10 = 30
Answer(s): (a) 20; (b) 18; (c) 30