7th Grade Algebra: Variables & Linear Functions Challenge

A store sells pencils for $0.50 each. If you buy x pencils, write an equation to represent the total cost. How much would it cost to buy 10 pencils?

• $2.00

• $7.50

• $5.00

• $10.00

Maria has 3 times as many marbles as John. If John has y marbles, write an equation to express the number of marbles Maria has. If John has 5 marbles, how many does Maria have?

• 10

• 15

• 25

• 20

A car rental company charges a flat fee of $20 plus $0.15 per mile driven. Write an equation to represent the total cost C for driving m miles. How much would it cost to drive 100 miles?

• $35

• $50

• $15

• $20

The perimeter P of a rectangle is given by the equation P = 2l + 2w, where l is the length and w is the width. If the length is 8 meters, write an equation to find the width w when the perimeter is 30 meters.

• w = 7 meters

• w = 3 meters

• w = 5 meters

• w = 10 meters

A school is planning a field trip. The cost per student is $15, and there are x students attending. Write an equation for the total cost T of the trip. If there are 25 students, what is the total cost?

• The total cost is $250.

• The total cost is $450.

• The total cost is $375.

• The total cost is $300.

The equation y = 2x + 3 represents a line. What is the y-value when x = 4?

• 7

• 11

• 15

• 9

A gardener is planting flowers in rows. If each row has x flowers and there are 5 rows, write an equation for the total number of flowers F. If there are 6 flowers in each row, how many flowers are there in total?

• 30

• 40

• 35

• 25

A bike shop sells bikes for $200 each. If you buy x bikes, write an equation for the total cost C. How much would it cost to buy 3 bikes?

• $200

• $800

• $600

• $400

The equation y = -x + 6 represents a linear function. What are the coordinates of the point where x = 2?

• (2, 6)

• (2, 4)

• (2, 2)

• (2, 0)

A recipe requires 2 cups of flour for every 3 cups of sugar. If you use y cups of sugar, write an equation for the amount of flour f needed. How much flour is needed if you use 9 cups of sugar?

• 10 cups of flour

• 8 cups of flour

• 6 cups of flour

• 4 cups of flour