Question

2.
Are the following numbers prime or composite. Show by finding the
factors.
(a) 9
(b) 48
(c) 89
(d) 96
(e) 78
(f) 101
Write down the first ten prime numbers.
3.
4.
Write down all the prime numbers between 50 to 110.
5.
A number lies between 2000 and 2070 and has 5 in its ones place. Is it a prime o
composite number? Give reasons.
6.
List the first five multiples of-
(a) 25
(b) 17
(c) 100 (d) 41
7.
List all the multiples of 15 between 50 to 100.
8.
Between which multiples of 10 does 3486 lie?
9.
Write any four pairs of twin primes.
10. Which of the following numbers are co-prime?
(a) 13, 14
(b) 8, 20
(c) 31, 59
(d) 34, 85​

Answer 1

Answer:

2. (a) 9 = 1 , 3 , 9 Composite No.

(b) 48 = 1 , 2 , 3 , 4 , 6 , 8 , 12 , 19 , 24 , 48   Composite No.

(c) 89 = 1 , 89   Prime No.

(d) 96 = 1 , 2 , 3 , 4 , 6 , 8 , 12 , 16 , 26 , 32 , 48 , 96   Composite No.

(e) 78 = 1 , 2 , 3 , 6 , 13 , 26 , 39 , 78   Composite No.

(f) 101 = 1 , 101   Prime No.