Adam's age is a multiple of 6 this year.
His age next year will be multiple of 5.
Adam's age is between 50 and 60.
- In how many years' time will Adam's age be a multiple of 7?
- How many years ago was Adam's age a multiple of 7?
(a)
Multiples of 6 (between 50 and 60): 54, 60
Multiples of 6 (+1): 43, 49, 55, 61
Multiples of 5: 50, 55, 60
Adam's age next year: 55Adam's age this year: 54Multiples of 7: 42, 49, 56
Adam's age when it becomes a multiple of 7 = 56
Number of years' time when Adam's age will be a multiple of 7
= 56 - 54
= 2
(b)
Multiple of 7: 42, 49
Least number of years ago when Adam's age was a multiple of 7
= 54 - 49
= 5
Answer(s): (a) 2; (b) 5