Estimating
Properties of Addition
Adding Decimals
Subtracting Decimals
Applications
Rounding
100

Estimate 9.74 + 111.06 by rounding to the nearest whole number.

121

100

Identify the addition property shown below:

(14 + 26) + 91 = 14 + (26 + 91)

Associative Property of Addition

100

19.23 + 0.099=

19.329

100

2.5 - 0.79 = 

1.71

100

Mrs. Tyson's math class held a bake sale to earn money to pay for a field trip. The field trip costs $350 total. During the bake sale, the pies generated $78.50, the cookies made $122.25, and the cakes brought in $95.75. How much more money does the class need to earn to pay for the field trip?

The class needs to earn $53.50 more.

100

Round to the place listed:

6.631; ones 

7
200

Estimate 7.32 - 0.53 by rounding to the highest place.

6.5
200

Identify the addition property shown below:

32 + 45 + 8 = 32 + 8 + 45

Commutative Property of Addition

200

5.79 + 21.9 =

27.69

200

19.23 - 7.27 = 

11.96

200

Jane collected 20.78 pounds of Halloween candy while trick or treating. Davis has 16.45 pounds of candy. About how much more candy does Jane have than Davis?

21-16=5

Jane has about 5 more pounds of candy than Davis.

200

Round to the place listed:

115.67; tenths

115.7

300

Estimate 188.78 - 63.2 by rounding to the highest place.

140

300

Identify the addition property shown below:

46.17 + 0 = 46.17

Identity Property of Addition

300

212.1 + 87.648 = 

299.748

300

14.3 - 6.88 =

7.42

300

For a school project, three students recorded how much water they drank each day for 3 days.  Their results are shown in the Water Journal table.

Bria set a goal to drink 10 litres of water each week. How much more water should Bria drink to meet her goal?

1.06 + 0.96 + 0.97 = 2.99 litres

10 .00 - 2.99 = 7.01 litres

Bria needs to drink 7.01 litres more throughout the rest of the week.

300

717.28; hundreds

700

400

Round to the place listed:

0.049; highest place

0.05