Question

The hcf of 72,81 and 99 is (a) 9 (b) 19 (c)29
Ans is 9

Answer 1

Answer:

Highest Common Factor(HCF) of 72,81 and 99 is 9.

Step-by-step explanation:

The highest common factor is obtained from the prime factorization of each of the numbers. We take the common primes in the prime factorization.

$72=2^3\times3^2\\81= 3^4\\99=3^2\times 11$

Here $3^2$ is a common factor in each of these prime factorization.

Hence

HCF(72,81,99) = 9.

Which means these numbers does not have a common factor bigger than 9.

So the correct option is (a).