1. 117 * 117 + 83 * 83 = ?
a) 20698
b) 20578
c) 21698
d) 21268
2. (1/4)3 + (3/4)3 + 3(1/4)(3/4)(1/4 + 3/4) =?
a) 1/64
b)27/64
c) 49/64
d)1
3. The difference of two numbers is 1365. On dividing the larger number by the smaller, we get 6 as quotient and 15 as reminder. What is the smaller number ?
a) 240
b) 270
c) 295
d) 360
4. The 7th digit of (202)3 is
a) 2
b) 4
c) 8
d) 6
5. H.C.F. of two numbers is 16. Which one of the following can never be their L.C.M
a) 32
b) 80
c) 64
d) 60
6. What is the remainder when 9^1+ 9^2 + 9^3 + …. + 9^8 is divided by 6?
a) 3
b) 2
c) 0
d)5
7. The sum of the first 100 natural numbers is divisible by
a) 2, 4 and 8
b) 2 and 4
c)2 only
d)none of these
8. For what value of ‘n’ will the remainder of 351n and 352n be the same when divided by 7?
a) 2
b)3
c)6
d)4
9. Let n be the number of different 5 digit numbers, divisible by 4 with the digits 1, 2, 3, 4, 5 and 6, no digit being repeated in the numbers. What is the value of n?
a) 144
b) 168
c)192
d)none of these
10. Find the greatest number of five digits, which is exactly divisible by 7, 10, 15, 21 and 28.
a) 99840
b) 99900
c)99960
d) 99990
Answer Key:
1.B; 2.D; 3.B; 4.C; 5.D; 6.C; 7.C; 8.B; 9.C; 10.C
Divisibility
1. A number is divisible by 2 if it is an even number.
2. A number is divisible by 3 if the sum of the digits is divisible by 3.
3. A number is divisible by 4 if the number formed by the last two digits is divisible by 4.
4. A number is divisible by 5 if the units digit is either 5 or 0.
5. A number is divisible by 6 if the number is divisible by both 2 and 3.
6. A number is divisible by 8 if the number formed by the last three digits is divisible by 8.
7. A number is divisible by 9 if the sum of the digits is divisible by 9.
8. A number is divisible by 10 if the units digit is 0.
9. A number is divisible by 11 if the difference of the sum of its digits at odd
places and the sum of its digits at even places, is divisible by 11.