Question

Which of the following numbers are co-prime?
r take(a) 18 and 35 (b) 15 and 37 (c) 30 and 415
(d) 17 and 68 (0) 216 and 215 (f) 81 and 16
11​

Answer 1

Step-by-step explanation:

(a) Factors of 18 = 1, 2, 3, 6, 9,18

Factors of 35 = 1, 5, 7, 35

Common factor =1

Since , both have only one common factor, i.e., 1, therefore, they are co-prime numbers.

(b) Factors of 15 = 1, 3, 5,15

Factors of 37 = 1, 37

Common factor = 1

since, both have only one common factor, i.e., 1, therefore, they are co-prime numbers.

(c) Factors of 30 = 1, 2, 3, 5, 6, 15, 30

Factors of 415 = 1, 5, 83, 415

Common factor = 1,5

Since , both have more than one common factor, therefore, they are not co-prime numbers

(d) Factors of 17 = 1, 17

Factors of 68 = 1, 2, 4, 17, 34, 86

Common factor = 1, 17

Since, both have more than one common factor, therefore, they are not co-prime numbers

(e) Factors of 216 = 1, 2, 3, 4, 6, 8, 36, 72, 108,216

Factors of 215 = 1, 5, 43, 215

Common factor =1

Since, both Have only one common factor, i.e , 1 , therefore they are co-prime numbers.

(f) Factors of 81 = 1, 3, 9, 27, 81

Factors of 16 = 1, 2, 4, 8, 16

Common factor = 1

Since, both have only one common factor, i.e., 1, therefore, they are co-prime numbers.