When estimating, you round the numbers and then calculate in your head.
This quickly gives you an approximate answer.
Example: 389 + 412
389 is almost 400, and 412 is almost 400.
So calculate 400 + 400 = 800.
The correct answer is close to 800.
Then choose the number that fits best.
The numbers filled in show the solution.
Example
- 800
- 300
For parents
What does this exercise practice?
Estimate results by rounding and use this to check your own calculations.
Common pitfalls
Children sometimes round in the wrong direction. Say it out loud: 389 is closer to 400 than to 300.
How to practice at home
While shopping, roughly round the prices and add them up in your head, then compare with the receipt.
Related: Rounding, Calculation, Find the error