Rounding & Estimating
Rounding whole numbers
rounding whole numbers means approximating it.
why round? a rounded whole number is often easier to use, understand, and remember the the precise whole number?
Rounding whole number given place value
locate the digit to the right of the given place value
if the digit is 5 or greater, add 1 to the digit in the given place value and replace each digit to its right by 0
if this digit is less than 5, replace it and each digit to its right by 0
Ex:
Estimating sums& Differences
You find the estimate of sums and differences by rounding addends, minuend, and subtrahends.
why? an estimated sum or difference can help us determine if we made a mistake in calculating an exact amount.
Ex:
rounds to