Question

The following two-way frequency table shows information collected from a survey of

students regarding their grade level and how they spend their screen time.
Grade vs. Uses the Watches Plays Video
Total
Screen Time Internet TV Games
7th Grader 6
3
6
15
8th Grader 8
3
2 13
Total 14
6
8
28
What is the probability that a student uses the Internet, given that he or she is in eighth
grade?
Enter your answer rounded to two decimal places, like this: 0.42

Answer 1

0.62

Explanation:

In the picture attached, the table is shown.

We want to find the probability that a student uses the Internet, given that he or she is in eighth grade. Mathematically:

P(Internet | eighth grade) = P(Internet ∩ eighth grade)/P(eighth grade)

P(Internet | eighth grade) = (8/28)/(13/28) = 8/13 = 0.62