Question

For each of the following numbers, find a composite number that is coprime to the given number. (a) 80 (b)63 (c) 135

Answer 1

a) 80 - 4
b) 63 - 8
c) 135 - 16

Answer 2

Answer:

We need to find the composite number that is co-prime to the given number.

Two numbers are said to be Co-prime numbers if and only if G.C.D of the two number is 1 i.e both the number has 1 as their common factor  

(a) 80 - 9 is the composite number which is co-prime to 80. since, 1 is the only common factor of 80 and 9.

(b) 63 - 16 is the composite number which is co-prime to 63. since, 1 is the only common factor of 63 and 16.

(c) 135 - 19 is the composite number which is co-prime to 135. since, 1 is the only common factor of 135 and 19.