Using Scientific Notation in Computation
Evaluate.
Express all numbers in scientific notation.
Commutative property
Product rule
Quotient rule
Simplify.
Write 0.2 in scientific notation.
Product rule
= 2000 Standard notation NOW TRY
= 2 * 103
= 12 10 -^12 104
=0.2* 104
=
1.92* 1.5
3.2* 4.5
* 104
=
1.92 1.5 103
3.24.5 10 -^1
=
1.92 1.5 106 * 10 -^3
3.2 4.5 10 -^5 * 104
=
1.92 106 1.5* 10 -^3
3.2 10 -^5 4.5* 104
1,920,000*0.0015
0.000032* 45,000
EXAMPLE 11
SECTION 5.1 Integer Exponents and Scientific Notation 273
Don’t stop
here!
Using Scientific Notation to Solve Problems
In 1990, private health care expenditures in the United States were $427 billion. By
2006, this figure had risen by a factor of 2.7— that is, it had risen by over times in
only 16 yr. (Source:U.S. Centers for Medicare & Medicaid Services.)
(a)Write the 1990 health care expenditure in scientific notation.
Write 427 in scientific notation.
Product rule
In 1990, the expenditure was
(b)What were expenditures in 2006?
Multiply the result in part (a) by 2.7.
Commutative and associative properties
Multiply.
Write 11.529 in scientific notation.
Product rule
Expenditures in 2006 were about $1,152,900,000,000 (over $1.1 trillion).
NOW TRY
= 1.1529* 1012
= 1 1.1529 1012 1011
= 11.529* 1011
= 1 2.7 4.27 2 1011
1 4.27 10112 2.7
$4.27* 1011.
=4.27 * 1011
= 1 4.27 1022 109
= 427 * 109 1 billion=1,000,000,000= 109
427 billion
(^2 12)
EXAMPLE 12
NOW TRY
EXERCISE 11
Evaluate.
0.00063*400,000
1400 *0.000003
NOW TRY
EXERCISE 12
The speed of light is approxi-
mately 30,000,000,000 cm per
sec. How long will it take
light to travel 1.2* 1015 cm?
NOW TRY ANSWERS
11.60,000
12.4.0* 104 sec,or 40,000 sec