Page 1
1.
The land area of the Earth is approximately 1.484 ·108 km2 . In 1980, the population of
the Earth was approximately 4,483,000,000. What was the population density (in
people/km2) of the Earth in 1980?
Round your answer to 2 decimal places.
2.
Simplify the expression. Express your answer using only positive exponents.
67
33
ab
ab
3.
Simplify the expression. Express your answer using only positive exponents.
( )( )
37
x y x y
4.
Simplify the expression. Express your answer using only positive exponents and
evaluate whenever possible.
( )
5
53
2xy
5.
Simplify the expression. Express your answer using only positive exponents.
5
11 4
6
ab
ab



6.
Simplify the expression. Express your answer using only positive exponents.
( )
( )
4
74
2
32
ab
ab
7.
Simplify the expression. Express your answer using only positive exponents.
8.
Use scientific notation to perform each computation. Write your answers in scientific
notation.
(5,900,000) (55,000,000)
Page 2
9.
Use scientific notation to perform each computation. Write your answers in scientific
notation.
( )( )
47
3.7 10 2.7 10••
10.
Use scientific notation to perform each computation. Write your answers in scientific
notation.
12
7
4 10
5.0 10
•
•
11.
Use scientific notation to perform each computation. Write your answers in scientific
notation.
455,000,000
5,000
12.
Simplify the expression. Express your answer using only positive exponents.
( )( )
2 6 4 2
–11 –4x y x y
13.
Simplify the expression. Express your answer using only positive exponents.
75
22
–20
4
xy
xy
14.
Simplify the expression. Express your answer using only positive exponents.
bc
fg
–20
5
xy
xy
15.
Simplify the expression. Express your answer using only positive exponents.
( )
6
4
–5ab
16.
Simplify the expression. Express your answer using only positive exponents.
5
43
7
16
4
xy
xy



Page 3
17.
Simplify the expression. Express your answer using only positive exponents.
( )( )
4
52
3 –6x y x y
18.
The atomic mass of an atom can be found by dividing the molar mass of the atom by
Avogadro’s number
( )
23
6.022142 10•
. The molar mass of hydrogen is 1.00797
g/mol. Find the mass of an atom of hydrogen. Express the answer in scientific
notation.
Page 4
Answer Key