Name:______________________________
Worksheet – Inverse Variation (2)
Inverse Variation in the Raw
1. Given that y varies inversely as x varies, and the constant of variation is 32, write the equation of variation.
2. In the inverse of variation equation xy=8.3, what is the constant of variation.
3. Suppose a situation where y varies inversely as x varies. Also, when x=4, y = 12. Given these facts, write the
equation of variation.
4. Use your equation of variation in problem 3 to determine the value of y when x = 6. Show a good set up and your
work.
5. Use your equation of variation from problem 3 to determine the value of x when y = 60.
6. Suppose a different situation where y varies inversely as x varies. Also, when y = 8, x = 1/4. Given these facts, write
the equation of variation.
Inverse Variation – Varying Pressure and Surface Area Over Using Constant Force.
7.
It is a law of physics that when one object presses on another it creates pressure on each other. If you keep the
force constant, the pressure will vary inversely as the surface area varies. Force is measure in Newtons and Surface
Area is measured meters2. (What we mean by surface area is the area of the point of contact. This is where the
objects are touching each other.). Suppose you have a 180 pound person standing on your back. Their force on you
in Newtons would be about 3900 N. Write an equation of inverse variation that reflects this situation.
8. Now consider that the surface area of the person’s normal walking shoes (this is both shoes together) is .04 meters2.
Determine the pressure the person exerts on you if they are standing on your back. (the unit for this is in
Kilopascals.)
9. Determine the pressure the same person exerts on you if they are standing on your back on one foot in the same
shoes.
10. Determine the pressure the person exerts on you if they change into a pair of high heels whose surface area is .018
meters2.
11. Determine the pressure the same person exerts on you if they are standing on your back on one foot in the same
shoes.
Review
Please simplify the following.
12. 7  y  9   4 y  63
12. 7  g  4    g  6
13. Please estimate 31% of 86.
14. Please estimate 11% of 640.