Chapter 2

Vocab please

100

The order of addends can be changed and the sum remains the same.

Commutative Property of Addition 

200

Addends can be regrouped and the sum remains the same.

Associative Property of Addition 

300

A process that determines which multiple of 10, 100, 1,000...a number is closest to

Rounding

400

Numbers that are easy to compute with mentally 

(Friendly Numbers)

Compatible Numbers

500

Adjusting one number of an operation to make computations easier and balancing the adjustment by changing the other number.

Compensation 

Let's Round!

100

Round the number to the nearest whole.

3.67

4

200

Round to the nearest tenth.

5.329

5.3

300

Round to the nearest thousandth

547.6754

547.675

400

Round to the nearest hundredth 

58.960

58.96

500

Round to the nearest tenth.

0.97

1.0

Add it up

100

32.9 + 43.92

76.82

200

85.3 + 17.05

102.35

300

0.654 + 0.837

1.491

400

543.9 + 23.34

567.24

500

95.978 + 3.345

99.323

Subtracting Fun

100

0.56 - 0.385

0.175

200

75.32 - 20.43

54.89

300

104.2 - 56.107

48.093

400

52.1 - 47.23

4.87

500

87 - 0.657

86.343

Challenge us!

100

if the 5 was underlined in 564,832

what would the rounded answer be?

600,000

200

If the 4 was underlined in 33,432

what would the rounded answer be?

33,400

300

57,699.792 + 2,974.493

60,674.285

400

56,443.87 + 166,765.9

223,209.77

500

68,961.353 - 4,363.007

64,598.346