Question:
If abc is a three-digit number, then number abc -a-b-c is divisible by
(a) 9
(b) 90
(c)10
(d) 11
Solution:
(d) We have, abc= 100a + 10b+c
.-. abc – a – b-c = (100a + 10b + c)-a – b-c = 100a – a + 10b – b = 99a + 9b = 9(11a + b)
Hence, the given number abc – a – b-c is divisible by 9.