1. Distance Speed and Time Calculating Speed Hrs and Min Calculating Distance Speed Distance or Time : Which Operation Hrs and Min Calculating Time Hrs and Min Hrs and Min : Intro

2. Speed Distance Time Distance = Speed x Time S = D ÷ T Speed = Distance ÷ Time D = S x T T = D ÷ S Time = Distance ÷ Speed D ST Units

3. DST … Distance D ST X To find Distance formula Cover D in DST triangle T = S D Distance = Speed x Time D = S x T Examples

4. DST …. Speed D ST S = D ÷ T Speed = Distance ÷ Time ÷ To find Speed formula Cover S in DST triangle S = D T = DT Examples

5. DST ….. Time D ST T = D ÷ S ÷ To find Time formula Cover T in DST triangle D T = DT S = Time = Distance ÷ Speed Examples

6. Units S D T Speed is the “key” when checking units A speed of 60 mph is 60 miles 1 hour60 mph 60 miles in 1 hour Distance must be in miles Time in hours

7. Units S D T Speed is the “key” when checking units A speed of 12m/s is 12 m 1 sec12 m/s 12 metre in 1 second Distance must be in metres Time in seconds

8. Units S D T 60 km 1 hr60 km/hr 60 km in 1 hour Speed is km/ hr

9. Units S D T 25 cm 1 sec25 cm/s 25 cm in 1 sec Speed is cm/ sec

10. 60 What’s the speed limit? At this speed, how far would you travel in 1 hour? 60 miles per hour 60 1234hrs 0 120 60 180 60 Same distance for next hour 60 After 2 hrs ….. 60 x 2 = 120 After 3 hrs ….. 60 x 3 = 180

11. 45 1 hour? miles per hour 45 1234hrs 0 90135 45 x 1 = 45 45 2 hour? 45 x 2 = 90 3 hour? 45 x 3 = 135 4 hour? 45 x 4 = 180 180 Start Next

12. Rule for Distance To find the distance travelled at a speed of S you multiply by the time taken for the journey DistanceSpeedTime = x D S T = x The next slide shows how to get this FORMULA from a DST triangle

13. Distance = 1206 D T x T S Time = 6 hour Speed = 120 km/hr Find rule for Distance 720 km D S = x D = x 6 120 D =

14. Distance= D ST X TS Time = 3 hr D = S x T 60X3 Speed= 60mph Find Distance D = S x T D = 180 miles

15. What can you find 1215 D S X T Time = sec D = S x T X Speed= m/s 180 miles 1512 D = = Can find distance

16. Finding Distance 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) x T D S T= S=100km/hr hr Distance D = S x T x S = D ÷ T = D ÷ S D= km ÷ ÷ Clear min T= 4 hr min

17. Parts of an Hour 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) New Speed Clear ¼ ½ ¾ 0.25 1 60 1 min dec 5 8 = 5 ÷ 8=0.625 9 18 27 36 0 Distance Travelled D = 36 x 0.75 = 27 hour Speed = 36 mph D = S x T

18. Parts of an Hour 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) New Example Clear 15 30 45 0.25 0.5 0.75 1 60 min dec Speed = 32 mph D = S x T = 2hrs ¼ ½ ¾ 1 hour 30min= 2.5 hrs = 3 hrs 15 min = 3 +0.25 hrs = 3.25 hrs Example

19. Finding Distance – Hrs and Min 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) x T D S T= S=32km/hr 3hr Distance D = S x T x S = D ÷ T = D ÷ S D= km ÷ ÷ Clear 15min T= hr min

20. Finding Speed 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) New Example Clear A train took hours to travel a distance of miles. If the train was travelling at the same rate then the speed in miles per hour is 4 hour = 180 hour = 180 ÷ 4 = 45 opposite of x is ÷ Each hour the train travels miles. Speed = Distance ÷ Time S D T = 4 180 x 45 Speed = 45 miles per hour

21. Finding Speed 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) x T D S T= S=km/hr hr D = S x T x S = D ÷ T = D ÷ S D=400 km ÷ ÷ Clear min T= 4 hr min New Example

22. Finding Speed … Hrs & Min 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) x T D S T= S=km/hr 1hr D = S x T x S = D ÷ T = D ÷ S D=96 km ÷ ÷ Clear 30min T= hr min New Example

23. Finding Time 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) x T D S T= S=20km/hr hr Find Time D = S x T x S = D ÷ T = D ÷ S D=80 km ÷ ÷ Clear min T= hr min

24. Finding Time Hrs Min 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) x T D S T= S=36km/hr hr Find Time D = S x T x S = D ÷ T = D ÷ S D=198 km ÷ ÷ Clear min T= hr min

25. Finding Speed, Distance or Time 01234 56789 1÷4 C. ÷x 0.25 + On ² - Ans = √ (-) x T D S 40 80 T= S=40km/hr hr D or S or T x T = D ÷ S T = 80 ÷ 40 T= 2 D=80 km ÷ ÷ Clear min T= hr min D ST Hrs D ST Hrs Min

26. Parts of an Hour 01234 56789 C. ÷x 0 + On ² - Ans = √ (-) New Example Clear 1 0.5 0.25 0.75 30 4515