Question

Determine the following product by suitable re-arrangement :

$8\times 125\times 40\times 25$.

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 $8\times 125=1000$ and $40\times 25=1000$.

So, we group the terms as given below :

$8\times 125\times 40\times 25=(8\times 125)\times (40\times 25)$

$$\begin{gathered} =1000\times 1000 \\ =1000000 \end{gathered}$$

Hence, the required product is $10,00,000$.