Adam's age is a multiple of 10 this year.
His age 8 years ago was a multiple of 4.
- What is Adam's age this year?
- What was Adam's age 3 years ago?
- What is Adam's age 5 years later?
Multiple of 10: 10, 20
Multiple of 10 (-8): 2, 12
Multiple of 4: 4, 8, 12
12 appears in both the multiples of 10 (-8) and the multiples of 4.
Adam's age 8 years ago = 12
(a) Adam's age this year = 20
(b) Adam's age 3 year ago = 20 - 3 = 17
(c) Adam's age 10 years later = 20 + 5 = 25
Answer(s): (a) 20; (b) 17; (c) 25