Time Distance Speed Calculations

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Time Distance Speed Calculations
Distance Speed Time
Units of Measure
Time
Hours
Minutes
There are 60 minutes in an hour so convert these
times in minutes to hours (in decimal notation).
Minutes to hours
Hours to minutes
Write as a fraction compared with 60 minutes (in
an hour)
Multiply by 60
30 60
30 minutes
0.5 hrs
2 hours
120 mins
2 60
15 60
15 minutes
0.25 hrs
0.75 hours
45 mins
0.75 60
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Time Distance Speed Calculations
Distance Speed Time
Units of Measure
Distance
Kilometres
Miles
Metres
Means
Speed
Kilometres per hour
km/hr
km/hr
Miles per hour
miles/hr
Metres per second
m/s
The calculation is given by the units of measure
Distance Time
Speed
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Time Distance Speed Calculations
Distance Speed Time
D S T

• Use this formula to find the distances for
• 20 miles per hour for 2 hours
• 60 miles per hour for 4 hours
• 40 kmph for 30 minutes
• 80 miles per hour for 15 minutes
• 42 km per hour for 10 minutes

40 miles
20 2
240 miles
60 4
40 30 60
20 km
80 15 60
20 miles
42 10 60
7 km
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Time Distance Speed Calculations
Distance Speed Time
Using what we have learnt from rearranging
equations
If
D

S
T

then
D

S
T

S
and
D

T

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Time Distance Speed Calculations
Speed Distance Time

• Use this formula to find
• A train travels 240 km in 4 hours
• What is its average speed?
• A plane flies over two cities that are 63 miles
  apart.
• The journey takes 7 minutes. What is its average
  speed?
• Answer in miles per minute
• 3. An athlete can run 100 metres in 12 seconds.
  Calculate the
• athletes speed.
• Answer in metres per second and 1 d.p.
• A cheetah took 6 seconds to run 150m. How fast
  did it run?
• Answer in metres per second

240 4
60 km per hour
63 7
9 miles per minute
100 12
8.3 m per second
150 6
25 m per second
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Time Distance Speed Calculations
Time Distance Speed

• Use this formula to find
• A man ran 400 m at an average speed of 8 m/s
• How long did he take?
• A coach travels 120 miles at an average speed of
  40 mph.
• How long did it take?
• A walker travels a distance of 3 km at a steady
  speed of 4km.
• Find how long he takes in minutes.
• A cyclist travelled 6 km at 18 kmph.
• Find how long he takes in minutes.

400 8
50 seconds
120 40
3 hours
3 4
0.75 hrs
45 mins
0.75 60
6 18
20 mins
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Time Distance Speed Calculations

• A delivery van sets off at 0745 to deliver a
  package 20 miles
• from the store. It arrives at the customer at
  0810
• Calculate the vans average speed in miles per
  hour
• The vans average speed on the return journey is
  25 mph.
• b) How long does the return journey take?
• Give your answer in minutes.
• c) Calculate the vans average speed for the
  whole journey.

25 60
20 0.4167
0.4167 hrs
48 miles per hour
20 25
0.8 hrs
48 mins
0.8 60
40 miles for (25 48) 73 minutes
73 60
40 1.2167
1.2167 hrs
32.9 miles per hour