A bus travels at 15 km/h. How long does 90 km take?
6 hours
Time = distance ÷ speed = 90 ÷ 15 = 6.
Day 049Distance and Time
Standards 6.RP.A.3b
LEARNING TARGET
I can solve constant-speed problems using a rate per hour.
01 · LEARN
Build the idea
At a constant speed, distance = speed × time. Divide distance by time to find speed, or distance by speed to find time. Keep units consistent before calculating.
A bus travels at 25 km/h. How long does 175/2 km take?
7/2 hours
Time = distance ÷ speed = 175/2 ÷ 25 = 7/2.
02 · PRACTICE
Your turn
Work in order. Start with the foundations, then build toward explanation and application.
A cyclist travels 120 km in 6 hours at constant speed. Find the speed.
A bus travels at 40 km/h. How long does 120 km take?
A cyclist travels 150 km in 6 hours at constant speed. Find the speed.
A bus travels at 10 km/h. How long does 60 km take?
A cyclist travels 240 km in 6 hours at constant speed. Find the speed.
A bus travels at 30 km/h. How long does 120 km take?
A cyclist travels 25 km in 5/2 hours at constant speed. Find the speed and the distance in 4 hours.
A bus travels at 35 km/h. How long does 70 km take?
A cyclist travels 20 km in 1 hours at constant speed. Find the speed and the distance in 2 hours.
A bus travels at 25 km/h. How long does 75/2 km take?
03 · CHECK
Answers and reasoning
Reveal the teacher answer key
- 20 km/h
Speed = 120 ÷ 6 = 20; distance = speed × time.
- 3 hours
Time = distance ÷ speed = 120 ÷ 40 = 3.
- 25 km/h
Speed = 150 ÷ 6 = 25; distance = speed × time.
- 6 hours
Time = distance ÷ speed = 60 ÷ 10 = 6.
- 40 km/h
Speed = 240 ÷ 6 = 40; distance = speed × time.
- 4 hours
Time = distance ÷ speed = 120 ÷ 30 = 4.
- 10 km/h; 40 km
Speed = 25 ÷ 5/2 = 10; distance = speed × time.
- 2 hours
Time = distance ÷ speed = 70 ÷ 35 = 2.
- 20 km/h; 40 km
Speed = 20 ÷ 1 = 20; distance = speed × time.
- 3/2 hours
Time = distance ÷ speed = 75/2 ÷ 25 = 3/2.