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5 votes
If a train travels m miles in h hours and 45 minutes, what is the average speed in miles per hour ?

a)  m / (h + 3/4 ), b) m / 7h, c) m ( h + 3/4 ), d) ( m + 45 ) / n, e) h / ( m + 45 )

2 Answers

4 votes

s=m \ miles\\ t=h \ hours \ 45 \ min=h+0.75 \ hours\\ v=(s)/(t)\\ v=(m)/(h+0.75) =(m)/(h+(3)/(4)) \Rightarrow A
User Dooburt
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7.6k points
2 votes
Speed = (distance covered) / (time to cover the distance).

Time = 'h' hours and 45 minutes.
45 minutes is 3/4 of an hour. (or 0.75 hour)
Total time is (h + 0.75) hours.

Speed = 'm' / (h + 0.75)

That's choice-'a'.
User Mike Spross
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6.7k points