Know Your Keywords — Math, Standard
Point 10 — Two-way probability table
What do we see?
A two-way probability table.
What do we understand?
- “What is the probability of ______ given that ______” — given is always followed by the information to use as the denominator.
- “If ______ is selected at random, then what is the probability” — the information in the blank becomes the denominator.
Question 1 of 3
At the fictional George Washington High School (GWHS), after-school activities can be classified into three types: athletics, fine arts, and other. The table gives the number of students participating in each of these types of activities by grade:
| 9th | 10th | 11th | 12th | Total | |
|---|---|---|---|---|---|
| Athletics | 150 | 160 | 140 | 150 | 600 |
| Fine arts | 100 | 90 | 120 | 125 | 435 |
| Other | 125 | 140 | 150 | 150 | 565 |
| Total | 375 | 390 | 410 | 425 | 1600 |
One of these students will be selected at random. What is the probability of selecting a student from the fine arts group, given that the participant is in grade 10?