Answer:
Option d - 720/750 ≈ 0.96
Explanation:
Given : Of 750 people surveyed, 330 were male and 640 had cell phones. Of those with cell phones, 390 were female.
To find : What is the probability that a person surveyed was either male or had a cell phone?
Solution :
Let M be the number of males i.e. M=330
Let C be the number of cell phones i.e C=640
Total number of people = 750
Of 750 people surveyed, 330 were male
The probability of male is

Of 750 people surveyed, 640 had cell phones
The probability of cell phones is

Of those with cell phones, 390 were female.
i.e. reaming were male so 640-390=250
So, Probability of male and cell phone is

We have to find, the probability that a person surveyed was either male or had a cell phone i.e.

Using formula,

Substitute the values,




Therefore, Option d is correct.