Question

Determine the following product by suitable re-arrangement :

$5\times 1764\times 20$.

Answer 1

As per the associative property of multiplication of the whole numbers, if $a,b$ and $c$ are any three whole numbers, then :

$(a\times b)\times c=a\times (b\times c)=a\times b\times c$.

We observe that $5\times 20=100$.

So, we first multiply $5$ and $20$ as shown below :

$5\times 1764\times 20=(5\times 20)\times 1764$

$$\begin{gathered} =100\times 1764 \\ =176400 \end{gathered}$$

Hence, the required product is $1,76,400$.