Chapter 9 Practice
Name ________________________
1. An apartment complex uses an average of
gallons of water each month. Each apartment in the
complex uses an average of
gallons each month. How many apartments are there in the
complex?
Evaluate the expression.
2.
Simplify the expression. Write your answer as a power.
3.
4.
5.
Evaluate the expression.
6.
7.
Write your answer in standard form.
8. A person breathes in about
cubic meters of air?
cubic meters of air per second. How long does it take to breathe in 2.1
Write the number in scientific notation.
9. 0.0000002626
10. 8,360,000
Multiply or divide. Write your answer in scientific notation.
11.
12.
6
13. (7.9  10 )
6
(1.98  10 )
14. About how many times greater is the thickness of a penny than the thickness of a dollar bill?
Item
Thickness
(in centimeters)
Penny
1.55  101
Nickel
1.95  101
Dime
1.35  101
Quarter
1.75  101
Half dollar
2.15  101
Dollar bill
1.0922  102
Write the product using exponents.
15.
16.
17. Carbon-14 dating is used by scientists to determine the age of a sample. The amount C (in grams) of a 50gram sample of carbon-14 remaining after t years is represented by the equation
. What
percent of the original amount will remain after 900 years?
Simplify. Write the expression using only positive exponents.
18.
19.
21.
22.
20.
23. Describe and correct the error in writing the number in standard form.
Find the area of the figure. Write your answer in scientific notation.
24.
7
7.6 × 10 cm
2.1 × 108 cm
Not drawn to scale
25. A blizzard drops 40 inches of snow in one day. At the end of each of the next three days, the depth of the
snow is
of the depth of the previous day. Write an expression for the depth of the snow after the third day
of melting. What was the depth (in inches)? Round your answer to the nearest tenth.
26. You build a model of the cube shown and make the sides 1.6 times as long. What is the value of x if the
volume of the model is 512 cm3.
27. The mass of a grain of sand is about
Use the table.
Unit of Mass
metric ton
gram. About how many grains of sand are in 100 kilograms of sand?
Mass
kg
gram
kg
milligram
kg
microgram
kg
28. How many grams are in a metric ton?
29. How many milligrams are in a metric ton?
30. A drop of water has a mass of 1 milligram. Its mass is 10,000,000 times greater than the mass of a red blood
cell.
a. Using the table above, what is the mass of the red blood cell in kilograms?
b. A nanogram is equal to
nanogram? Explain.
gram. Is the mass of the red blood cell less than, greater than, or equal to one
31. The power of a space shuttle is the combined force of the thrusters multiplied by the velocity.
The velocity of the shuttle is
meters per second. What is the power (in newton-meters per second)
of the shuttle?
Force = 3.1 × 10
7
N
32. Suppose the average grain of salt weighs about 0.000058 gram. What is the weight (in grams) of 9 million
grains of salt?
33. A jet aircraft is traveling at a speed of
meters per minute.
a. How many meters does the jet travel in 9 minutes? Write your answer in scientific notation.
b. How many kilometers does the jet travel in 100 minutes? Write your answer in scientific notation.
34. The table shows the speed of sound through various substances.
Iron
Copper
Helium
Sea water
Substance
Speed (km/h)
1.8
1.3
3.5
5.5
a. Through which substance does sound travel fastest?
Gold
1.2
b. Through which substance does sound travel slowest?
35. The distance between two cities is 7000 kilometers.
a. One kilometer is 10 millimeters. What is the distance between the two cities in millimeters?
b. Two other cities are 7  10 millimeters away from each other. Are these two cities closer or father away
from each other than the other two cities? Explain.
Chapter 9 Final Test - Answer Section
1. ANS: 72
2. ANS: 32
3. ANS:
4. ANS:
5. ANS:
6. ANS:
1
16
7. ANS: 1
8. ANS: 8,400 sec
9. ANS:
10. ANS:
11. ANS:
12. ANS:
0
13. ANS: 4.0  10
14. ANS: about 14.19 times greater
15. ANS:
16. ANS:
17. ANS: a. about 44.88 g
18. ANS:
19. ANS:
20. ANS:
b. about 89.76%
21. ANS:
22. ANS:
𝑡 3 𝑥2
65
23. ANS: The negative exponent means the decimal point will move left, not right, when the number is written
in standard form.
24. ANS:
25. ANS:
cm
; 11.9 in.
26. ANS: x = 5
27. ANS: 100,000,000 grains of sand
28. ANS: 1,000,000 g
29. ANS: 1,000,000,000 milligrams
30. ANS: a.
kg
b. The mass of the red blood cell is less than one nanogram. One nanogram is equal to
31. ANS:
Newton-meters per second
32. ANS: 522 g
33. ANS: a. 1.17 × 105 m
34. ANS: a. iron
b. 1.3 × 103 km
b. helium
35. ANS: a. 7  10 millimeters
b. closer; The numbers have the same factor and the exponent 8 is less than the exponent 9.
kilogram.