Question

Which of the folowing numbers is not divisible by 4?
(a) 78536
(b) 1264
(c) 6421
(d) 7935

Answer 1

A number is divisible by 4 if the number's last two digits are divisible by 4.
In (a) 78536 and (b) 1264, the last two digits 36 and 64 respectively are divisible by 4.
Therefore, (a) 78536 and (b) 1264 are divisible by 4.
In (c) 6421 and (d) 7935 the last two digits 21 and 35 respectively are not divisible by 4.
Therefore, (c) 6421 and (d) 7935 are not divisible by 4.