If the LCM of P and 18 is 36 and the HCF of P and 18 is 2, then P equals:
(4)
We know that LCM (a, b) × HCF (a, b) = a × b
⇒ LCM (P, 18) × HCF (P, 18) = P × 18
⇒ 36 × 2 = P × 18 ⇒ 72 = 18P
⇒ P = 72 ÷ 18 = 4