In an examination, 5% of the applicants were found ineligible and 85% of the eligible candidates belonged to the general category. If 4275 eligible candidates belonged to other categories, then how many candidates applied for the examination?
The choices are as follow:
30,000
35,000
37,000
None of these
Kindly help me solve this problem. I'm a first year college student taking up an algebra class and I'm really having trouble with translating word problems into equation. I tried to solve this but my answer doesn't match the answer keys in this problem.
4275 + 85/100x + 5/100x = x [total # of candidates]
x = 4275.9 <–my answer is none of these but the answer key says otherwise, that the answer is 30,000. It shows the solution:
x = number of aplicants
95% of x = number of eligible applicants
eligible candidates of each categories = 15% of (95% of x) –> (57/400)x
therefore, (57/400)x = 4275
x = 30,000
I can't understand why the answer key looks for the 15% of the eligible candidates in both categories when it should only look for 10% (which represents the candidates in "other categories") of the 95% of x (since the 85% belongs to the general category).
Best Answer
Your looking at the question innaccurately. Take it slowly and break it down.
First take the first part
What does this tell you? It tells you that 5% were ineligible and 95% were eligible. Let x be the number of total applicants, and e be the number of eligible candidates. We would get the following formula
Now we look at the next line
This is saying 85% of e (not x) belong to the general category. So letting n be the number of people not in the general category we would get
We are then given n
So we have
Thus we have
And plugging this into our previous equation we get
Hope that helps a little more.
Edit Where does 85/15 come from?
Let e = eligible, n = non-generally eligible, and g = generally eligible. So we have
What we are trying to do is convert g to n since we don't know what g is. We do know that:
Thus we get that
And that's where we get the 85/15. Basically think of it as "how much bigger is g than n?". If n is 15% of e and g is 85% of e then g is (85/15) times bigger than n so we get (85/15)n = g.
2nd edit
Why can't we convert (5/95) to (5/100)x?
Because of the following:
You can put it all into one nice equation, but you can't just flop things around without going line by line to see what everything does.