Rounding a number means to change its value slightly so it is not as exact as the original number. Numbers are rounded to a certain place value - tens, hundreds, thousands. etc..
Numbers are rounded to make it easier to do various math processes such as estimating costs in one's head or dividing larger numbers.
RULE: To round a two digit number or higher number to the nearest tens place:
If the number in the ones place of a two digit number is less than five, round the number down to the nearest tens place. If the number in the ones place is greater than five, round it up to the nearest tens plac.
Example 1: Round 23 to the nearest tens place
The number 3 in the ones place is less than five. Therefore the number 23 is rounded down to 20. 23 rounded to the nearest tens place is 20.
Example 2: Round 28 to the nearest tens place.
The number 8 in the ones place is greater than five. Therefore the number 28 is rounded up to 30. 28 rounded to the nearest tens place is 30.
Example 3: Round 94 to the nearest tens place.
The number 4 in ones place is less than five. Therefore the number 94 is rounded down to 90. 94 rounded to the nearest tens place is 90.
Example 4: Round the number 97 to the nearest tens place.
This one is tricky. The number 7 in the ones place is greater than five. Therefore the number 97 is rounded up to 100. 97 rounded to the nearest tens place is 100.
