Mathematics
NULL
Medium
Question
A box contains nine bulbs of which 4 are defective. If four bulbs are chosen at random, find the probability that at least one bulb is good.
A
62/63
B
124/126
C
125/126
✓ Official correct answer
D
1/126
Community credibility
Registered members can vote for the answer they believe is correct today and explain why. If the facts change after an election or news event, suggest a new option so others can vote it up.
A
62/63
No member explanations yet for this option.
B
124/126
No member explanations yet for this option.
C
125/126
No member explanations yet for this option.
D
1/126
No member explanations yet for this option.
Explanation
1 − C(4,4)/C(9,4) = 1 − 1/126 = 125/126.