Question

Using the common multiple method, find the $L.C.M.$ of the following:

$3,6,9$ and $12$

Answer 1

Step 1: Find the multiples

Multiples of $3=3,6,9,12,15,18,21,24,27,30,33,36,.....$
Multiples of $6=6,12,18,24,30,\mathrm{36....}$
Multiples of $9=9,18,27,36,,....$​
​Multiples of $12=12,24,36\dots ..$ (1 mark)

Step 2: Find the $L.C.M.$
Common multiples of $3,6,9$ and $12=36,72,\dots$​ (0.5 mark)
$\therefore L.C.M.$ of $3,6,9$ and $12=36.$ (0.5 mark)
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