Question

If HCF(98, 28) = m and LCM(98, 28) = n, then the value of n - 7m is ______.

विकल्प

• 0

• 28

• 98

• 196

Answer 1

If HCF(98, 28) = m and LCM(98, 28) = n, then the value of n - 7m is 98.

Explanation:

Step 1: Find HCF (98, 28)

The highest common factor (HCF) is the greatest number that divides both 98 and 28.

Prime factorisation: 

98 = 2 × 7 × 7

28 = 2 × 2 × 7

Common factors: 2 and 7

HCF = 2 × 7 = 14

m = 14

Step 2: Find LCM (98,28) 

The least common multiple (LCM) is found using the formula:

LCM (a, b) = `(a ×b)/("HCF" (a,b))`

LCM( 98,28) = `(98 × 28)/14 = 2744/14 = 196`

n = 196

Step 3: Compute n − 7m

= n − 7m = 196 − (7×14)

= 196 − 98

= 98

The value of n − 7m is 98.