Question

Test the divisibility of the following numbers by 4:

(i) 786532
(ii) 1020531
(iii) 9801523

Answer 1

Rule: A natural number is divisible by 4 if the number formed by its last two digits is divisible by 4.

(i) Here, the number formed by the last two digits is 32 which is divisible by 4.
Thus, 7,86,532 is divisible by 4.

(ii) Here, the number formed by the last two digits is 31 which is not divisible by 4.
Thus, 10,20,531 is not divisible by 4.

(iii) Here, the number formed by the last two digits is 23 which is not divisible by 4.
Thus, 98,01,523 is not divisible by 4.