which numbers are co-prime . a. 15,31 b.17,68 c. 30,405 d. 3,9
Answers
Answer:
a) 15 and 31
Step-by-step explanation:
Co-primes are the numbers that have no common factors other than 1.
a) 15 and 31 have no common factors, so they are co-primes.
b) 17 and 68 have 17 as common factor. So, they are not co-primes.
c) 30 and 405 have 5 as common factor. So, they are also not co-primes.
d) 3 and 9 have common factor 3. So, they are not co-primes.
HOPE THIS ANSWER HELPS U ....
PLEASE MARK IT AS BRAINLIEST....
Answer:
a) Factors of 18 = 1, 2, 3, 6, 9, 18
Factors of 35 = 1, 5, 7, 35
Common factor = 1
Since, both the numbers have only one common factor, i.e., 1, therefore, they are co-prime number.
(b) Factors of 15 = 1, 3, 5, 15
Factors of 37 = 1, 37
Common factor = 1
Since, both the numbers have only one common factor, i.e., 1, therefore, they are co-prime number
(c) Factors of 30 = 1, 2, 3, 5, 6, 15, 30
Factors of 415 = 1, 5, …….., 83, 415
Common factor = 1, 5
Since, both the numbers have more than one common factor, therefore, they are not co-prime number.
(d) Factors of 17 = 1, 17
Factors of 68 = 1, 2, 4, 17, 34, 86
Common factor = 1, 17
Since, both the numbers have more than one common factor, therefore, they are not co-prime number.
(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 the numbers have only one common factor, i.e., 1, therefore, they are co-prime number.
(f) Factors of 81 = 1, 3, 9, 27, 81
Factors of 16 = 1, 2, 4, 8, 16
Common factor = 1
Since, both the numbers have only one common factor, i.e., 1, therefore, they are co-prime number.
----------------------------------------------------------------------------------------------------Hence (a) , (b) , (e) & (f) are co-prime.-------------------------------------------------------------------------------------------------Hope this will help you......