SKILL: USING PERCENTAGES
MATH TUTORIAL
CLASSZONE.COM
Click on Math Tutorial
for more help with the
percent equation.
How Much Would You
Weigh on Other Worlds?
When astronauts walked on the Moon, they felt much lighter than
they felt when they were on Earth. Neil Armstrong’s total mass—
about 160 kilograms with space suit and backpack—did not change.
However, the Moon did not pull as hard on him as Earth did, so he
weighed less on the Moon. At the surface, the Moon’s gravitational
pull is only 17% of Earth’s gravitational pull. You can use percentages
to calculate Neil Armstrong’s weight on the Moon.
Example
On Earth, with his heavy space suit and backpack, Neil Armstrong
weighed about 1600 newtons (360 lb). To calculate his weight
on the Moon, find 17% of 1600 newtons.
“Of” means “multiply.”
17% of 1600 N = 17% 1600 N
Change the percent to
a decimal fraction.
Simplify.
= 0.17 1600 N
= 272 N
ANSWER With his suit and backpack, Neil Armstrong weighed
about 270 newtons on the Moon.
Use the percentages in the table to
answer the following questions.
Percent of Weight on Earth
1. A backpack weighs 60 newtons
(13 lb) on Earth. (a) How much
would it weigh on Jupiter?
(b) How much would it weigh
on Jupiter’s moon Io?
Mercury
38
Venus
91
Earth
100
2. (a) How much would a student
weighing 500 newtons (110 lb)
on Earth weigh on Saturn?
(b) on Venus?
3. On which planet or moon would
you be lightest?
This picture of Buzz Aldrin on
the Moon was taken by Neil
Armstrong, who can be seen
reflected in Aldrin’s helmet.
748 Unit 6: Space Science
CHALLENGE A pencil weighs
0.3 newtons (1 oz) on Earth.
How much would it weigh on
the Moon? If an astronaut let
go of the pencil on the Moon,
would the pencil fall? Explain.
Planet or Moon
%
Moon (Earth)
17
Mars
38
Jupiter
236
Io (Jupiter)
18
Europa (Jupiter)
13
Ganymede (Jupiter)
15
Callisto (Jupiter)
13
Saturn
92
Titan (Saturn)
14
Uranus
89
Neptune
112
Triton (Neptune)
8.0
Pluto
6.7
Charon (Pluto)
2.8