Find the greatest number that divides 90, 180 and 240 exactly.

Correct option is D

Given:

Numbers are 90,180 and 240

Solution:

The greatest number that divides the numbers is called HCF or highest common factor.

HCF of 90, 180 and 240 is:

90 =$$2 \times 3^2 \times 5$$​​

180 = $$2^2 \times 3^2 \times 5$$​​

240 =$$2^4 \times 3 \times 5$$​​

HCF = Common factors = $$2 \times 3 \times 5 = 30$$​​