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The length of time it takes college students to find a parking spot in the library parking lot follows a normal distribution with a mean of 4 minutes and a standard deviation of 1 minute. Find the probability that a randomly selected college student will take between 2.5 and 5 minutes to find a parking spot in the library lot.

User Ajevic
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1 Answer

3 votes

Answer:

the probability that a randomly selected college student will take between 2.5 and 5 minutes to find a parking spot in the library lot is 0.77454

Explanation:

Given that:

mean = 4

standard deviation = 1

The objective is to find the probability that a randomly selected college student will take between 2.5 and 5 minutes to find a parking spot in the library lot.

i.e


P(2.5 \leq x \leq 5) = P((2.5 - \mu)/(\sigma) \leq (X-\mu)/(\sigma)\leq (5- \mu)/(\sigma))


P(2.5 \leq x \leq 5) = P((2.5 - 4)/(1) \leq Z \leq (5- 4)/(1))


P(2.5 \leq x \leq 5) = P((-1.5)/(1) \leq Z \leq (1)/(1))


P(2.5 \leq x \leq 5) = P({-1.5}\leq Z \leq 1)


P(2.5 \leq x \leq 5) = P({Z < 1})- P(Z < -1.5)


P(2.5 \leq x \leq 5) = 0.84134- 0.06680


\mathbf{P(2.5 \leq x \leq 5) = 0.77454}

User Fralau
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