Adam's age is a multiple of 5 this year.
His age 3 years ago was a multiple of 8.
Adam's age is between 30 and 40.
- In how many years' time will Adam's age be a multiple of 6?
- How many years ago was Adam's age a multiple of 10?
(a)
Multiple of 5: 5, 10, 15, 20, 25, 30, 35
Multiple of 5 (-3): 2, 7, 12, 17, 22, 27, 32
Multiples of 8: 8, 16, 24, 32
Adam's age this year = 35
Multiples of 6: 6, 12, 18, 24, 30, 36
Number of years' time when Adam will be a multiple of 6
= 36 - 35
= 1
(b)
Multiples of 10: 10, 20, 30
Least number of years ago when Adam's age was a multiple of 10
= 35 - 30
= 5
Answer(s): (a) 1; (b) 5