Question

An astronaut weighs 170 pounds on Earth but only 68 pounds on Mars. While visiting the planet, the astronaut removes a rock sample that weighs 25 pounds on Mars.

What is the weight of the rock sample on Earth?
Help me solve.


a. 0.22
b. 4
c. 0.5
d. not enough info.

Answer 1

Answer: 62.5 pounds

Explanation:

Given: An astronaut weighs 170 pounds on Earth but only 68 pounds on Mars.

The weight of the rock sample on Mars = 25 pounds

Since the "Weight of object on Mars"is directly proportional to "Weight of object on Earth".

`\Rightarrow\ \frac{\text{Weight of rock sample on Earth }}{\text{Weight of rock sample on Mars}}=\frac{\text{Weight of astronaut on Earth}}{\text{Weight of astronaut on Mars}}\\\\\\\Rightarrow\ \frac{\text{Weight of rock sample on Earth }}{25}=(170)/(68)\\\\\\\Rightarrow\ \text{Weight of rock sample on Earth }=(170*25)/(68)=62.5`

Hence, the eight of the rock sample on Earth = 62.5 pounds

Answer 2

The ratio of the man's weights on Earth and Mars should be equal to the ratio of the rocks weight on Earth and Mars. By letting x be the stone's weight on Earth, the equation that best describe the condition is,
(170 pounds / 68 pounds) = (x pounds / 25 pounds)
The value of x is 62.5 pounds. If the units of the choices in the pounds then, it is not among the choices.