Write an Equation

1
Write an Equation
COURSE 3 LESSON 7-5
Sound travels at about 1.1 ? 103 ft/s. How far
does a sound travel in 11 s?
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2
Write an Equation
COURSE 3 LESSON 7-5
(continued)
d (1.1 ? 103) 11
The sounds travels 1.21 ? 104 feet.
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3
Write an Equation
COURSE 3 LESSON 7-5
(continued)
The exponent on 10 for the distance is 4. This is
larger than the exponent on 10 for the rate.
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4
Write an Equation
COURSE 3 LESSON 7-5
A certain blood sample contains 3 ? 1012 red
blood cells. If there are 5 ? 1010 red blood
cells in 1 milliliter of blood, about how many
milliliters of blood are in this sample?
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5
Write an Equation
COURSE 3 LESSON 7-5
(continued)
b (5 ? 1010) 3 ? 1012
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6
Write an Equation
COURSE 3 LESSON 7-5
(continued)
There are about 60 milliliters of blood in the
sample.
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7
Write an Equation
COURSE 3 LESSON 7-5
Write an equation to solve each problem. 1. A
space probe travels at 1.5 ? 105 m/h. How far
does it travel in 32 days? 2. Light travels at
3 ? 108 m/s. How many seconds does a light ray
take to travel 1.8 ? 1011 m?
1.152 ? 108 m
600 s
7-5