1. Speed, Distance, Time Calculations

2. The objective of this lesson is to be able to use the correct formulas to calculate speed, distance or 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 Speed, Time & Distance:
Speed x
Time
Solving for Speed
Solving for Time
Solving for Distance D S T
Remember them from
this triangle:

5. Answer: His speed was 16 km / hour
A windsurfer travelled 28 km in 1 hour 45 mins.
Calculate his speed.
Distance
Time D S T
Speed = 28
1•75 =
1 hour 45 mins
= 16 km/h
Answer: His speed was 16 km / hour

6. Let’s Try It!
Speed = ?
Distance = 25miles
Time = 10minutes D S T

7. Let’s Try It!
Speed = ?
Distance = 15km
Time = 8min. D S T

8. Let’s Try It!
What is the speed of a car that traveled 150 miles in 2.5 hours? D S T

9. Your Turn!
Speed = ?
Distance = 39m
Time = 20sec D S T

10. Your Turn!
Speed = ?
Distance = 235m
Time = 120sec D S T

11. Your Turn!
If a train travels 1500m in 250sec, how fast is the train traveling? D S T

12. 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 S T
Distance =
Speed x Time
= 50 x 2•5
2 hour 30 mins
= 125 km
Answer: He travelled 125 km

13. D=180 m Let’s Try It! Speed = 12m/s Time = 15s Distance Traveled = ? D

14. Let’s Try It!
Kiarra walks to school in the morning. It takes her 12 minutes to get to school when she walks at a speed of 3 miles per hour. How far does Kiarra live from school?
D=0.6mi. D S T

15. D=40.8 mi. Your Turn! Speed = 12mi./hr. Time = 3.4 hrs
Distance Traveled = ?
D=40.8 mi. D S T

16. Your Turn!
Jacob rides his bike to school. When he pedals at a speed of 4 meters per second, it takes him 9 minutes to get to school. How far does Jacob live from school?
D=2160m D S T

17. Your Turn!
When Chris takes the bus to school, it takes him 15 minutes to get to school. If the bus is traveling at a speed of 25 miles per hour, how far does Chris live from the school?
D=6.25 mi. D S T

18. 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 S T
Distance
Speed
Time =
555 60 =
= 9•25 hours
= 9 hours 15 mins
Answer: It took 9 hours 15 minutes

19. T=3.58hrs Let’s Try It! Distance = 251 miles Speed = 70 mi/hr Time = ?

20. Your Turn!
Distance = 235 km
Speed = 42km/hr
Time = ?
T=5.59hrs D S T

21. Your Turn!
Beth is part of the school track team. She runs the 500 meter at a speed of 7 meters per second. What was her final time at the end of the race?
T=71.42s D S T

22. Your Turn!
Erica decides to walk home from school with her friends. If her house 1540 meters from school and she walks at a speed of 1.5 meters per second, how long will it take her to walk home? How many minutes would that be?
T= s or
T=17.11min D S T