Question

Estimate $717-123$ by rounding to nearest tens.

• A. $600$
• B. $500$
• C. $400$

Answer 1

The correct option is A $600$

To round off any number to the tens place, we observe the Ones place.

Here, for $717$, the place value of ones place is $7$ which is more than $5$. So we round it up to $720$.

For $123$, the place value of ones place, $3<5$ so we round it down to $120$.

Now subtracting our rounded off numbers we get $720-120=600$ which is a great estimation, very close to the original value of $717-123=594$