Speed / Distance X Time

[dsryan]

Hi guys,

I have a test coming up as a part of a entrance into the Police service. All they require is basic maths that you learn in school -- which I seem to have forgotten!

I need help with the not-so-obvious.

For example; a car travelling at 70mph for 1 hr has obviously travelled a distance of 70 miles.

I'm stuck on the not soo obvious ones and was hoping some of you could maybe answer a few questions, showing working, to help me understand the method. So without further adu;

A car travelling at 72mph for 42 minutes covers how many miles?

A car has travelled 42 miles and it took 2 hours 12 minutes, what was its speed?

A car is going 26mph, it has covered 8 miles. How long did it take in minutes?

Probably very simple, but I'm tearing my hair out trying to figure it out! Haha.

Thanks in advance!

 

[dsryan]

Bump

 

[Ishuda]

Knowing what you want and what you have can help.

For example the first problem:
You have:
72 miles per hour = 72 m/h
42 minutes = 42/60 h
You want m (miles). If I multiply those two givens together, the hours (h) will cancel out and I'll be left with m. So.
72 * 42/60 = ? miles

The second problem
You have
42 m
2 hrs 12 min = 2 hrs + 12/60 hrs = 2.2 h
You want m/h. If I divided the traveled by the time I will have m/h
42/2.2 = ? m/h

and so forth. Sometimes it is easier to get an answer and convert it. For example (at the tip says), the third problem. Get the hours then convert to minutes.