1. Distance, Rate (speed), Time
How to Calculate Each

2. The aim of this lesson is to be able to use the correct formulas to calculate distance, rate (speed), time

3. 15 mins = 0.25 hour 30 mins = 0.5 hour 45 mins = 0.75 hour
Reminder: How to change minutes into a decimal
15 mins = 0.25 hour
So: 3 hours 15 mins = 3.25 hours
30 mins = 0.5 hour
So: 7 hours 30 mins = 7.5 hours
45 mins = 0.75 hour
So: 2 hours 45 mins = 2.75 hours

4. The 3 formulas for Rate, Time & Distance:
Rate x
Time
Solving for Rate
Solving for Time
Solving for Distance D R T
Remember them from
this triangle:

5. d=____________ r=____________ t=_____________
A windsurfer travelled 28 km in 1 hour 45 mins.
Calculate his rate.
d=____________
r=____________
t=_____________ D R T

6. Answer: His rate (speed) was 16 km / hour
A windsurfer travelled 28 km in 1 hour 45 mins.
Calculate his rate.
Distance
Time D R T
Rate = 28
1•75 =
1 hour 45 mins
= 16 km/h
Answer: His rate (speed) was 16 km / hour

7. d=____________ r=____________ t=_____________
A salesman travelled at an average speed of 50 km/h for 2 hours 30 mins. How far did he travel?
d=____________
r=____________
t=_____________ D R T

8. Answer: He travelled 125 km
A salesman travelled at an average speed of 50 km/h for 2 hours 30 mins. How far did he travel? D R T
Distance =
Rate x Time
= 50 x 2•5
2 hour 30 mins
= 125 km
Answer: He travelled 125 km

9. d=____________ r=____________ t=_____________
A train travelled 555 miles at an average speed of 60 mph. How long did the journey take?
d=____________
r=____________
t=_____________ D R T

10. Answer: It took 9 hours 15 minutes
A train travelled 555 miles at an average speed of 60 mph. How long did the journey take? D R T
Distance
Rate
Time =
555 60 =
= 9•25 hours
= 9 hours 15 mins
Answer: It took 9 hours 15 minutes

11. Let’s try one together! d=____________ r=____________ t=_____________
A car travels along a road at a steady speed of 60 mph. How far will it travel in 6 hours?
d=____________
r=____________
t=_____________ D R T

12. You Try! d=____________ r=____________ t=_____________
A train covers a distance of 480 mi in 8 hours. If it travels at a constant speed, how fast is it traveling?
d=____________
r=____________
t=_____________ D R T

13. You Try! d=____________ r=____________ t=_____________
John walks at a steady speed of 3 mph. How long will it take him to travel 24 miles?
d=____________
r=____________
t=_____________ D R T

15. Your Turn to Teach!
Each partner set will have a teacher and a student. The teacher will explain to the student how to complete the chart below and help the student to solve for the variable.
Helen ran an 8-kilometer race in 52 minutes. What was her average speed?
d=____________
r=____________
t=_____________ D R T

16. SWITCH
Switch roles! Again, the teacher will explain to the student how to complete the chart below and help the student to solve for the variable.
A car goes 45 mph and travels for 200 miles. How many hours will it take for the car to reach its destination?
d=____________
r=____________
t=_____________ D R T