A study was done to find if different tire treads affect the braking distance of a car.

Identify the Independent Variable

The time it takes to run a mile depends on the person’s running speed.

Identify the Dependent Variable

The height of bean plants depends on the amount of water they receive.

Identify the Dependent Variable

The higher the temperature of the air in the oven, the faster a cake will bake.

Identify the Independent Variable

The amount of pollution produced by cars was measured for cars using gasoline containing different amounts of lead.

Identify the Independent Variable

A student wanted to test how the mass of a paper airplane affected the distance it would fly. Paper clips were added before each test flight. As each paper clip was added, the plane was tested to determine how far it would fly.

Identify the Dependent Variable

An experiment was performed to determine how the amount of coffee grounds could affect the taste of coffee. The same kind of coffee, the same percolator, the same amount and type of water, the same perking time, and the same electrical sources were used.

Identify the Independent Variable

The boss thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, the boss counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks.

Identify the Dependent Variable

The boss thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, the boss counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks.

Identify the Independent Variable

The boss thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, the boss counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks.

Identify the Control Variable