Problem solving with direct and inverse proportion

12 questions

1. Two variables are in ___ proportion if they have a constant multiplicative relationship.
2. Which graph shows no proportional relationship?
3. y \propto x^2, when y=192, x=4. Work out the value of y when x=10.
4. Which of these graphs show y \propto \frac{1}{x^n}?
5. y \propto \sqrt{x}, when y=40, x=4. Work out the value of y when x=100.
6. y \propto \frac{1}{x^2}, when y=9.6, x=5. Work out the value of y when x=10. Give your answer as a decimal.
7. Two variables are inversely proportional if there is a constant ___ relationship between one variable and the reciprocal of the other.
8. When y\propto \sqrt{x}, when x, increases by 96%, what proportion does y increase by?
9. Given the following proportions, select which are the correct proportional relationships when : a \propto c, c \propto b, b \propto \frac{1}{e} and a \propto \frac{1}{f}.
10. When y \propto x and x \propto z^2, when y=75, x=3 and when x=128, z=4. Write y in terms of z.
11. When y\propto x^2, when x increases by 20%, what proportion does y increase by?
12. Match the graph with the equations.

License: OGL