Basic Math Examples

$656 - 521$

Step 1

Round $656$ to $650$ .

$650 - 521$

Step 2

Round $- 521$ to $- 500$ .

$650 - 500$

Step 3

Subtract $500$ from $650$ .

$150$

Step 4

The approximate value of $656 - 521$ found by front end estimation.

$656 - 521 \approx 150$