Find the probability that a student finishes in more than 12 minutes. Draw and shade the distribution to interpret your results.

Question

Suppose the time is takes for 20 statistics students to complete this quiz is uniformly distributed from 0 minutes to 15 minutes

Answer 1

The problem is asking about a continuous or cumulative distribution where P (x > 12 minutes) and can be answered by using the cumulative density function as (x-a)/(b-a). There is one additional detail, we are looking the probability of the outcome being greater than 12 minutes, so we will need to subtract are previous result from 1 using the concept of the complement of a set.

P (x ≤ 12) = (12-0)/(15-0)= 12/15 =.80

Thus the P (x > 12) = 1 - .80 =.20 or 20% chance