In a certain town, 10% of people commute to work by bicycle. If a person is selected randomly from the town, what are the odds against selecting someone who commutes by bicycle?
A) 9 : 1
B) 9 : 10
C) 1 : 9
D) 1 : 10

Question

Quizplus · Accepted Answer

Odds against an event = (Probability of the event not happening) : (Probability of the event happening) = (1 - P(event)) : P(event). Here, P(commuting by bicycle) = 10% or 0.1, so odds against = (1 - 0.1) : 0.1 = 0.9 : 0.1 = 9 : 1.

In a Certain Town, 10% of People Commute to Work