WEBVTT
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What distance would a car travelling at 171 kilometres per hour for 38 minutes cover?
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The easiest way to answer a question like this is to use our speed–distance–time triangle.
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In this question, we’re given a speed of 171 kilometres per hour.
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We are also given a time of 38 minutes.
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We can therefore calculate the distance travelled by multiplying the speed or velocity by the time.
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A common mistake here would be to multiply 171 by 38.
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However, we can’t do this.
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The speed is in kilometres per hour, but our time is in minutes.
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We know that 60 minutes is equal to one hour, so we need to convert 38 minutes into hours.
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To convert from minutes to hours, we can write the number of minutes as a fraction over 60.
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Therefore, 38 minutes is 38 over 60 hours.
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Whilst it is not essential in this case, we could simplify this fraction to 19 over 30 by dividing the numerator and denominator by two.
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We can now calculate the distance that the car travels by multiplying 171 by 38 over 60.
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Typing this into our calculator gives us an answer of 108.3.
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A car travelling at a speed of 171 kilometres per hour for 38 minutes will cover a distance of 108.3 kilometres.