Independent and Dependent Variables

Molly investigated if the age of students caused them to be better drivers. She found that their skill of driving changed based on the age of the student. What is the independent variable?

• Type of car

• Skill of driving

• Age of student

Robert wanted to know if the type of phone you used gave you better or worse service. The type of service changes based on the type of phone you have. What is the dependent variable.

• Location of phone call

• Type of phone

• How good or bad the service was

Marcos wants to know: Does the type of gasoline put in a car effect how fast the car can drive? The type of gasoline put in the car determines how fast the car goes. What is the independent variable?

• Type of gasoline

• which car the gas is put into

• how fast the car can drive

• how much gas is put into the car

Bob earned $8 for every cake he delivers. The amount of money he earned depends on the number of cakes he delivers.

m = money

c = cakes he delivers

The dependent variable is:

• m = money

• c = cakes he delivers

Carrie gets one sticker for every paper she completes. The number of papers she completes determines the number of stickers she gets.

s = stickers

p = paper

The independent variable is:

• s = stickers

• p = paper

Tim got 3 pieces candy for every house he trick or treated at. The number of candies he gets changes based on the number of houses he goes to.

c = candy

h = house

The dependent variable is:

• c = candy

• h = house

Norman gets one treat every time he jumps. The number of jumps he does determines how many treats he gets.

t = treats

j = jumps

The independent variable is:

• t = treats

• j = jumps

Sophie earned $1 for every she got an A on her report card. The amount of money she gets changes based on the number of A's she gets on her report card.

m = money

A = A on report card

The dependent variable is:

• m = money

• A = A on report card

Lily got one prize for every book she read. The number of books she reads determines the number of prizes she gets.

p = prize

b = books she reads

The independent variable is:

• p = prize

• b = books she reads

How does watching TV during studying affect a student’s test grades? The amount of hours a student watches TV determines the student's test grade.

• independent

• dependent