Grade 7 | Unit 5 | Lesson 12: Negative Rates | Practice Problems

Describe a situation where each of the following quantities might be useful. -20 gallons per hour.

• Water leaking out of a tank

• River flow rate

• Fuel consumption during vehicle idle

• Aquarium water change rate

Describe a situation where each of the following quantities might be useful. -10 feet per minute.

• An airplane descending

• An elevator moving

• A fan blade rotating

• A car moving in reverse

Describe a situation where each of the following quantities might be useful. -0.1 kilograms per second.

• Gravel being emptied out of a truck

• A balloon deflating

• Snow melting

• Sand being poured from a height

A submarine is only allowed to change its depth by rising toward the surface in 60-meter stages. It starts off at -340 meters. At what depth is it after 1 stage?

• -280 meters

• -300 meters

• -320 meters

• -340 meters

A submarine is only allowed to change its depth by rising toward the surface in 60-meter stages. It starts off at -340 meters. At what depth is it after 2 stages?

• -220 meters

• -280 meters

• -260 meters

• -240 meters

A submarine is only allowed to change its depth by rising toward the surface in 60-meter stages. It starts off at -340 meters. At what depth is it after 4 stages?

• -100 meters

• -140 meters

• -160 meters

• -180 meters

A submarine is only allowed to change its depth by rising toward the surface in 60-meter stages. It starts off at -340 meters. How many stages will it take to return to the surface?

• 5 stages

• 6 stages

• 6.5 stages

• 7 stages

A motor boat traveled -3.4 miles per hour for 0.75 hours. How far did it go?

A tugboat traveled -1.5 miles in 0.3 hours. What was its velocity?

A cookie recipe uses 3 cups of flour to make 15 cookies. How many cookies can you make with this recipe with 4 cups of flour?