Adam's age is a multiple of 7 this year.
His age 2 years ago was a multiple of 9.
Adam's age is between 50 and 60.
- 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 6?
(a)
Multiple of 7: 7, 14, 21, 28, 35, 42, 49, 56
Multiple of 7 (-2): 5, 12, 19, 26, 33, 40, 47, 54
Multiples of 9: 9, 18, 27, 36, 45, 54
Adam's age this year = 56
Multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60
Number of years' time when Adam will be a multiple of 6
= 60 - 56
= 4
(b)
Multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54
Least number of years ago when Adam's age was a multiple of 6
= 56 - 54
= 2
Answer(s): (a) 4; (b) 2