Question

If HCF and LCM of two numbers are 0.5 and 2.5 respectively and one of the numbers is 2.0, what is the other number?

• A. 0.825
• B. 0.625
• C. 0.25
• D. 2.5

Answer 1

The correct option is B

0.625

Let the two numbers be a and b.
For any two numbers a and b,
a x b = (LCM of a and b) x (HCF of a and b)
$\Rightarrow$ 2 x b = 2.5 x 0.5
$\Rightarrow$ b = $\frac{2.5\times 0.5}{2}$
$\Rightarrow$ b = 0.625
Hence the other number is 0.625.