Ratio and proportion
posted by Alex L. on .
About 9 out of 10 adults think it is a good idea to exercise regularly. But the ones who think it is a good idea, only 1 in 6 actually exercises at least 3 times a week. At this rate, how many of the 300 employees in our company exercise regularly?
What I did so far was write this:
9/10 = x/300
x=270

That's a good start.
1/6 = x/270 
The answer depends upon how one defines "regularly". If they mean "at least three times a week", the answer is
(9/10)*(1/6)*300 = 45 
(1/6)(9/10)(300)
= 45
not really a proportion problem 
How do I state this question?
Is it..
 At least 45 employees exercise regularly out of that rate 
About 45 employees in the company exercise regularly

It's because of the different rates that confuse me.

well, 9/10 of the 300 want to do it
and (1/6) of that (9/10) actually do it
so 1/6 * 9/10 * 300