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45 votes
45 votes
4.There are 30 students in the classroom competing for classroom prizes. Only the first two students whose name is drawn will win a prize. The first student wins 5 bonus points and the second student wins 2 bonus points, both on the upcoming test. If you are one of the 30 students, what is the probability you will win the top prize and your best friend wins the second prize?

User Bendihossan
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1 Answer

11 votes
11 votes

Out of 30 students, the probability of one student winning the top prize is 1/30.

Since the student who won the top prize cannot be the student who wins the second prize, then the probability of a student winning the second prize is 1/29.

So, the probability that you will win the top prize and your best friend wins the second prize is:


P=(1)/(30)*(1)/(29)=(1)/(870)

Answer:

The probability that you will win the top prize and your best friend wins the second prize is 1/870.

In decimal form, this is 0.001149.

In percent form, this is approximately 0.11%.

User Thisarattr
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