help needed

10% of motorist who exceed the speed limit gets a ticket
20% of motorist who exceed the speed limit doesn't get a ticket

What about the other who exceed the speed limit?
Either you have a ticket or not, I don't understand these percentages.

pepeprepa wrote:10% of motorist who exceed the speed limit gets a ticket
20% of motorist who exceed the speed limit doesn't get a ticket

What about the other who exceed the speed limit?
Either you have a ticket or not, I don't understand these percentages.

They get two tickets!

I agree, there's something wrong with the question as posted.

this was a question that i got on ETS's powerprep. the answer is 12.5%. i just don't know how to arrive to the said answer

OK, we can reverse engineer the actual question based on the answer.

Here's how the question actually reads:

On a certain road, 10% of all motorists get a ticket, and 20% of motorists who exceed the speed limit don't get a ticket. If no non-speeders get tickets, what is the percent of motorists on that road that exceed the speed limit?

So, if 20% of speeders don't get tickets, that means that 80% of speeders do get tickets.

Therefore:

10% = 80% of all speeders

1/10 = 4/5 (S)
1/10* 5/4 = S
5/40 = S
1/8 = S

and, when we convert 1/8 to a percent, we get 12.5%.

cheers