Question

Estimate the following sums by rounding off the numbers to their nearest thousands and compare the result with the actual sum.

b) $2,507+3,223$

Answer 1

To round off the digit to the nearest thousand, only hundred digit we have to see, if the hundred digit is more then $5$,then in the thousand digit one is added and other place value digit is change to zero. And if the value is less then $5$, then the thousand digit remain same and other place value will change to zero.

So,$2,507$ is written as $3,000$.

$3,223$ is written as $3,000$.

Sum of the round off thousand $$\begin{gathered} =3,000+3,000 \\ =6,000 \end{gathered}$$

Actual sum $$\begin{gathered} =2,507+3,223 \\ =5,730 \end{gathered}$$

Round off actual sum is $6,000$.

Both the result is same.