Topic 4 Review

Powers of 10

100

0.086 x 10³

86

200

42.3 x 0.01

0.423

300

0.9463 x 100

94.63

400

Hope runs 3.35 miles each day. How many total miles will Hope run have ran after 10 days?

33.5 miles

500

Choose all equations that are true.
a. 4.82 x 1,000=482,000
b. 4.82 x 10²= 482
c. 0.482 x 10¹=48.2
d. 0.482 x 10³=482
e. 0.0482 x 10⁴=4,820

B and C

Estimating Decimals

100

Estimate 59 x 0.19

12

(60 x 0.2)

200

Estimate 0.12 x 105

10

(0.10 x 100)

300

Estimate 99.2 x 82

8,000

(100 x 80)

400

Round to the nearest whole number: 8.3 x 7.5

64

(8 x 8)

500

Rounding to the nearest tenth, which of the following gives an underestimate?
a. 39.45 x 1.7
b. 27.54 x 0.74
c. 9.91 x 8.74
d. 78.95 x 1.26
e. 18.19 x 2.28

B and C

Multiply decimals x a whole number

100

5 x 0.5

2.5

200

4 x 0.15

0.6

300

0.25 x 5

1.25

400

1.25 x 3

3.75

500

4 x 0.36

1.44

Multiply decimals x decimals

100

0.2 x 0.8

0.16

200

0.5 x 0.7  

0.35

300

2.4 x 0.7

1.68

400

Which two factors would give you a product of 0.4?

0.9, 0.5, 80.1, 0.8, 9, 5

0.5 and 0.8

500

What is the missing factor in ____ x 0.7= 0.287
a. 0.041
b. 0.41
c. 4.1
d. 41

b. 0.41

Miscellaneous

100

Is this decimal placement correct? If not, what is the correct placement?

0.6 x 0.7= 0.042

Incorrect; 0.42

200

What exponent makes this expression true?

68 x 10^?=68,000

3

300

Sandra is 56.43 inches tall. On her fifth birthday, she was 43.27 inches tall. How much has she grown since her fifth birthday?

13.16 inches

400

The number 0.06 is 1/10 of which decimal?

a. 0.006
b. 0.06
c. 0.6
d. 6.0

c. 0.6

500

An auditorium has 29 rows of chairs with 115 chairs in each row. How many chairs does the auditorium have in all?

3,335 chairs