Question

What is the least common multiple of $9$ and $15$?

Answer 1

Ans. $45$

Explanation:

First we need to write out the prime factors of $9$ and $15$

$9:3\times 3$

$15:\left(3\right)\times \left(5\right)$

Next we take the largest group of each number:

$9$ has two $3s$ while $15$ has $15$

We multiply the largest group together:

$LCM(9,15)=3\times 3\times 5=45$

$\frac{45}{15}=3,\frac{45}{9}=5$