Question

15, 21, 35 ,Find g.c.d. and l.c.m.

Answer 1

GCD (Greatest common divisior) (HCF) (Highest Common Factor) of two or more numbers= Product of the smallest Power of each common prime factor involved in the numbers.
LCM (least common multiple) of two or more numbers = product of the highest Power of each factor involved in the numbers.
SOLUTION :
15, 21, 35
Prime factors of 15 = 5 × 3
Prime factors of 21 = 7¹× 3¹
Prime factors of 35 = 7¹× 5¹

GCD (15,21,35) = 1
LCM (15,21,35) = 5 × 7 × 3= 105
LCM (15,21,35) = 105

Hence, the GCD is 1 & LCM is 105

HOPE THIS ANSWER WILL HELP YOU...

Answer 2

Hi ,

We have ,

15 = 3 × 5

21 = 3 × 7

35 = 5 × 7

HCF( 15,21,35 ) = 1

[ Product of the smallest power of each

common prime factors of the numbers ]

LCM( 15, 21 , 35 ) = 3 × 5 × 7

[ Product of the greatest power of each

prime factors of the numbers ]

= 105

Therefore ,

HCF = 1 ,

LCM = 105

I hope this helps you.

: )