Question

. Find the greatest common factor and the least common multiple of each of the following sets of numbers. 12 and 7

Answer 1

LCM = 84 GCF = 1

Explanation:

LCM of 7 and 12 is 84.

GCF(7,12) = 1

LCM(7,12) = ( 7 × 12) / 1

LCM(7,12) = 84 / 1

LCM(7,12) = 84

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).

GCF of 7 and 12 is 1. Now calculate the prime factors of 7 and 12, then find the greatest common factor (greatest common divisor) of the numbers.

To find the GCF of two numbers: List the prime factors of each number. Multiply those factors both numbers have in common. If there are no common prime factors, the GCF is 1.

Answer 2

HCF: 1

LCM: 84

Explanation:

7 is a prime number. Nothing but 1 and 7 divide into which means that twelve and 7 have no highest common factor but 1.

The lowest common multiply (because 12 and 7 are prime to each other ) is 12 * 7 = 84