SOLUTION: An experienced teacher writes an exam so that, on average, about 5% of students will earn an A grade. If she has 50 students in her class and their performance is independent, what

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Question 1135830: An experienced teacher writes an exam so that, on average, about 5% of students will earn an A grade. If she has 50 students in her class and their performance is independent, what is the probability that at least one student gets an A?
Answer by VFBundy(438) About Me  (Show Source):
You can put this solution on YOUR website!
Determine the probability that NONE of the students receives an 'A':
0.95%5E50+=+0.0769

Subtract this result from 1 to determine the probability that AT LEAST ONE of the students receives an 'A':
1+-+0.0769+=+0.9231

There is a 92.31% chance that at least one of the students receives an 'A'.