Question

A traffic study has shown that the probability that 5 cars will pass over a small bridge in a 4-minute period is 0.16.What are the odds against exactly 5 cars passing over the bridge in that time?

Answer 1

A probability is the number of outcomes divided by the number of total outcomes.

An odd is given by a:b, in which a is the number of successes and b is the number of failures.

From the question, the probability of 5 cars will pass over a small bridge is 0.16

That means the total outcomes is 100 and the outcomes of successes are 16

Then to find the failures subtract 16 from 100

The failures = 100 - 16 = 84

Successes = 16

a = 16

Failures = 84

b = 84

Odds = a: b

Odds = 16: 84

Divide each term by 4 to simplify

Odds = (16/4): (84/4)

Odds = 4: 21

The answer is 4: 21