The lesson is about problems involving inverse variation

2. Translate each of the following into
mathematical equation. Use k as the
constant of variation.
1. The height (h) of a circular cylinder of a
given volume is inversely proportional to the
square of the radius (r).
2. To balance a seesaw, the weight (w) is
inversely proportional to the distance (d)
from the fulcrum.

3. Translate each of the following into
mathematical equation. Use k as the
constant of variation.
3. The weight (w) of a body varies inversely
as the square of the distance (d) from the
center of the Earth.
4. At a constant temperature, the volume (V)
of a gas varies inversely as the pressure (P)
upon it.

4. Identify whether the given is Inverse or
Direct Variation. Find k and the equation of
Variation.
x 10 15 6 5 3
y 3 2 5 6 10
x 4 5 6 8 12
y 28 35 42 56 84
x 30 40 50 60 80
y 4 3 2.4 2 1.5

6. Find the constant of variation and the
equation:
1.y varies inversely as x and y = 6 when
x = 18.
2.y varies inversely as x and y = 15 when
x = 2/5.
3.y varies inversely as x and y = - 12
when x = - 3

7. SOLVE FOR THE INDICATED VARIABLE IN
EACH OF THE FOLLOWING
1.If y varies inversely as x and y = 10
when x = 2, find y when x = 10.
2.Suppose a varies inversely with b.
When b = 4 and a = ½, find a when b =
18.

8. SOLVE FOR THE INDICATED VARIABLE IN
EACH OF THE FOLLOWING
3. The number of hours t required to finish
a certain job varies inversely as the
number of persons n on the job. If 16
persons require 18 hours to finish the job,
how long would it take 64 persons to
finish the job?