Use estimates to check answers
2nd Grade Math practice: A student says 52 + 29 = 101. Does that seem reasonable. Part of compare and estimate (Compare and Estimate).
~10 min
An estimate helps you see if an exact answer is reasonable.
Round to nearest ten
To round to the nearest ten, find the two tens your number is between and choose the nearer ten. If the ones digit is 5 or more, round up; if it is 4 or less, round down.
💡 Look at the ones digit to decide.