Information and Communication Technology - Number System
- Option : D
- Explanation : ∴165 + 215 = (24)5 + 215 =220 +215
= 215 (32 + 1)= 33x 215
Hence, it is divisible by 33.
39. If 78*3945 is divisible by 11, where * is a digit, then * is equal to
- Option : D
- Explanation : A number is divisible by 11, if the difference of the sum of its digits at odd places and the sum of its digit of even " places, is either 0 or a number divisible by 11.∴ (5 + 9 + * + 7) - (4 + 3 + 8) = 0 or multiple of 11 ⇒ (21 + *) - 15 = 0 or mUltiple of 11. ⇒ 6 + * = 0 or multiple of 11. ⇒ * + 6 =a multiple of 11. ⇒*+6=11 ⇒ *=5
40. The number which can be written in the form of n(n + 1)(n + 2), where n is a natural number, is
- Option : D
- Explanation : Given, n(n + l)(n + 2) Now, putting n = 1. we have 1 (1 + 1) (1 + 2)= 1 x 2 x 3 = 6
