MHB What is the Average Speed of a Train Traveling 18 km in 20 Minutes?

AI Thread Summary
The average speed of a train traveling 18 km in 20 minutes is calculated by converting the time into hours, resulting in 0.333 hours. Using the formula for average speed, v = d/t, the calculation yields an average speed of 54 kilometers per hour. The discussion emphasizes the importance of using fractions instead of decimals for clarity in calculations. Participants highlight that the recurring decimal can be avoided by using the fraction 1/3. Overall, the average speed determination is straightforward when using the correct time conversion.
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The total distance traveled by trains is 18 km & the time spent is 20 minutes. Find the average speed of the train in kilometers per hour.

I' m stuck right in the beginning in converting 20 minutes to hours by dividing from 60 which I get this recurring decimal 0.33333
 
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You don't need a decimal value...

$$\overline{v}=\frac{d}{t}=\frac{18\text{ km}}{\dfrac{1}{3}\text{ hr}}=54\text{ kph}$$
 
MarkFL said:
You don't need a decimal value...

$$\overline{v}=\frac{d}{t}=\frac{18\text{ km}}{\dfrac{1}{3}\text{ hr}}=54\text{ kph}$$
Thanks :D The times when you got to decide between fractions and decimals
 

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