Question

One week a librarian kept track of whether returned books were returned on time or not, and whether they had fewer than 200 pages or they had 200 pages or more. The results are shown in the table.
What is the probability that a randomly selected book returned that week was returned on time, given that it had 200 pages or more?



Returned on time
fewer than 200 pages—— 78
200 pages ir more ——116


Returned late
Fewer than 200 pages ——15
Returned late ——31

Answer 1

Answer:

0.4833

Step-by-step explanation:

We want GIVEN THAT 200 pages or MORE AND RETURNED ON TIME.

Returned on time

fewer than 200 pages—— 78

200 pages ir more ——116

Returned late

Fewer than 200 pages ——15

Returned late ——31

The first table is returned on time and last row is 200 pages or more, so we take that value "116".

To get probability, we also need the total. We add up all those 4 values:

78 + 116 + 15 + 31 = 240

Thus, probability is = 116/240 = 0.4833