Question

The high school parade band rehearses with either 7 or 10 members in each line. What is the least number of members that can be present in the marching band ?

• A. $35$
• B. $70$
• C. $105$
• D. $50$

Answer 1

The correct option is B $70$

In each row, the number of members can be $7$ or $10.$

$\therefore$ The least number of members in the marching group will be the LCM of $7$ and $10$.

So, the LCM of both numbers will be the product of both numbers as both are co-prime numbers.

$\therefore$ LCM $=7\times 10=70$.

So, minimum $70$ members can be present in the marching band.