Estimate by rounding:
345 + 528
Estimate as: 300 + 500 = 800
127 x 34
Estimate as: 130 x 30 = 3900
78 ÷ 6
Estimate as: 80 ÷ 6 = 13
Using compatible numbers:
235 + 487
Estimate as: 240 + 480 = 720
85 x 32
Estimate as: 80 x 30 = 2400
126 ÷ 9
Estimate as: 120 ÷ 10 = 12
