Question

Estimate the following using general rule : $9250\times 29$

Answer 1

Estimating the multiplication

The given expression is : $9250\times 29$

The general rule is that we have to round off each number to its greatest place.

Here, the first number's highest place value is thousand so we will round off it to nearest thousand and second number's highest place value is tens so we will round off it to nearest ten.

For rounding off to nearest thousands, we first check the digit at hundred's place. If the digit at hundred's place is less than $5$ then replace hundred's, ten's, one's place by zero but if the digit at hundred's place is $\ge 5$ then we add $1$ to thousand's place digit and replace hundred's, ten's, one's place by zero.

$9250\to 9000$

For rounding off to nearest tens, we first check the digit at one's place.If the digit at one's place is less than $5$ then we replace it by zero but the digit at one's place is $\ge 5$ then we add $1$ to ten's place digit and replace one's place by zero.

$29\to 30$

Now,

$\begin{array}{rcl}9250\times 29& =& 9000\times 30\\ & =& 270000\end{array}$

Hence, estimation of the product $9250\times 29$ is $270000$.