SHG to Ratio and Proportion page 7

The Singing Hedgehog Guide to:
Ratio and Proportion 7

Here is a final example for a popular type of question:

A car travels at 45km/h.
What is this in m/s?

We need to realise that 45km/h means 45 kilometres in 1 hour.
We can now, as usual, write the question as a ratio:

	distance	:	time
	45km	:	1 hr = 60 mins	work towards the objective of seconds
work towards the objective of metres	45/60km = 0.75km = 750m	:	1 min = 60 secs	divide by 60 to get 1 minute
	750/60m = 12.5m	:	1 sec	divide by 60 again to get 1 sec

So we find the answer to be 12.5 m/s