Estimating Sums
Materials: numeral cards (0-9)
______________________________________________________________________________- Turn over six cards to make two 3-digit numbers.
- Estimate the sum of the two numbers by rounding each number to
the nearest hundred and adding them mentally. - Repeat with other pairs of 3-digit numbers.
Example: 400 400 + 3 00 = 7 00
300
(^)
4 1
2
9
9
4
ver. 2