Speed, Distance & Time
Speed, Distance, Time
Calculations
The objective of this
lesson is to be able to use
the correct formulas to
calculate speed, distance
or time.
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
The 3 formulas for Speed, Time & Distance:
Distance
Speed =
Time
Solving for Speed
Time =
Distance
Speed
Solving for Time
Distance = Speed x Time
Solving for Distance
D
Remember them from
this triangle:
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A windsurfer travelled 28 km in 1 hour 45 mins.
Calculate his speed.
Speed =
=
Distance
Time
28
1•75
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1 hour 45 mins
= 16 km/h
Answer: His speed was 16 km / hour
Let’s Try It!
• Speed = ?
• Distance = 25miles
• Time = 10minutes
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Let’s Try It!
• Speed = ?
• Distance = 15km
• Time = 8min.
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Let’s Try It!
• What is the speed of a car that traveled 150
miles in 2.5 hours?
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Your Turn!
• Speed = ?
• Distance = 39m
• Time = 20sec
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Your Turn!
• Speed = ?
• Distance = 235m
• Time = 120sec
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Your Turn!
• If a train travels 1500m in 250sec, how fast
is the train traveling?
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A salesman travelled at an average speed of 50 km/h for
2 hours 30 mins. How far did he travel?
Distance = Speed x Time
= 50 x 2•5
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2 hour 30 mins
= 125 km
Answer: He travelled 125 km
Let’s Try It!
• Speed = 12m/s
• Time = 15s
• Distance Traveled = ?
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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?
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Your Turn!
• Speed = 12mi./hr.
• Time = 3.4 hrs
• Distance Traveled = ?
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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?
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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?
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A train travelled 555 miles at an average speed
of 60 mph. How long did the journey take?
Distance
Time =
Speed
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=
555
60
=
9•25 hours = 9 hours 15 mins
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Answer: It took 9 hours 15 minutes
Let’s Try It!
• Distance = 251 miles
• Speed = 70 mi/hr
• Time = ?
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Your Turn!
• Distance = 235 km
• Speed = 42km/hr
• Time = ?
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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?
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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?
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