3

Set 1: Probability (Beginner)

Explanation

Answer: D

PROBLEM

A bag contains 21 balls, 18 of which are green. What is the probability of randomly selecting a green ball?

A bag contains 21 balls, 18 of which are green. What is the probability of randomly selecting a green ball?

A.

6/21

B.

15/21

C.

7/6

D.

6/7

✓ Correct

Detailed Explanation

Choice D is the best answer. P = favorable/total = 18/21 = 6/7

Why others are wrong:
A: 6/21 is incorrect because it does not satisfy the equation.
B: 15/21 is incorrect because it does not satisfy the equation.
C: 7/6 is incorrect because it does not satisfy the equation.