# What is the LCM of 10 and 4?

Jan 8, 2017

$L C M = 20$

#### Explanation:

multiples of $10 : \left\{10 , \textcolor{red}{20} , 30 , 40 , 50 , \ldots\right\}$

multiples $4 : \left\{4 , 8 , 12 , 16 , \textcolor{red}{20} , 24 , 28 , 32 , 36 , 40 , \ldots\right\}$

common multiples$\left\{20 , 40 , \ldots .\right\}$

The first shared value is 20 so LCM = 20

Jan 9, 2017

20

#### Explanation:

Multiply 10 by any whole number and the last digit will be 0. So we need the first multiple of 4 that will give a 0 as the last digit.

This is $4 \times 5 = 20$

So the LCM = 20