The least common multiple of 18 and 24 is: (a) 36 (b) 72 (c) 54 (d) 108

Step-by-step solution

1. Prime factorise 18: $18=2\times 3^2$.
2. Prime factorise 24: $24=2^3\times 3$.
3. For LCM, take the highest power of each prime: $2^3$ from 24 and $3^2$ from 18.
4. Multiply these highest powers: $2^3\times 3^2=8\times 9=72$.
5. Thus the LCM is 72.

Concept tested: Least common multiple

Published 13 October 2026 · How this solution was prepared and checked