On a certain road 10 percent of the motorists exceed the posted speed limit and receive speeding tickets, but 20 percent of the motorists who exceed the posted speed limit do not receive speeding tickets. What percent of the motorists on the road exceed the posted speed limit?
20% exceed and get a ticket, so 80% speed and dont get a ticket
let x = total motorists. 10% of which speed and get tickets
so 80% of x= 10% or .8x=.10 or 80x=10
x=10/80 = .125 or B) 12.5%
Hope that made sense.