The LCM of two numbers is five times their HCF. If the product of the two numbers is 20480, then find their HCF and LCM, respectively.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 64 and 320.
L.C.M = 5 × H.C.F
Let the two numbers be a and b
We know that
L.C.M × H.C.F = a × b
⇒ 20480 = 5 × H.C.F × H.C.F
⇒ 20480/5 = H.C.F2
⇒ 4096 = H.C.F2
⇒ H.C.F = 64
⇒ L.C.M = 5 × 64 = 320