Estimate Decimal Sums and Differences

Round to the nearest WHOLE number to find the sum: 34.87 + 20.41

Round to the nearest WHOLE number to find the sum:

44.56 + 14.72

Round to the nearest TEN to find the sum:

19.36 + 12.88

Round to the nearest WHOLE number to find the difference:

324.61 - 211.87

Round to the nearest HUNDRED to find the difference:

576.76 - 231.84

Estimating is finding a value that is CLOSE or APPROXIMATE to the actual value, but it's not exact.

Roughly, approximately, and about are all clues for knowing when to round or estimate.

What is the symbol used when rounding/estimating?

What are compatible numbers?

Choose a good pair of compatible numbers to make finding the sum of 223.4 + 148.9 easier to add mentally.