Question

What is the sum of LCM and HCF of 45, 75?

• A. 225
• B. 240
• C. 250
• D. 215

Answer 1

The correct option is B 240

45 = 3 $\times$ 3 $\times$ 5
75 = 3 $\times$ 5 $\times$ 5
LCM of 45 and 75 is $3\times 3\times 5\times 5=225$
Product of two numbers = Product of their HCF and LCM
$HCF=\frac{45\times 75}{225}=15$
Sum of LCM and HCF = 225 + 15 = 240