From tech troubles to travel tips, IDNLearn.com has answers to all your questions. Ask any question and get a thorough, accurate answer from our community of experienced professionals.

the grades in an exam were normally distributed with a mean of 80 and standard deviation of 4 . what is the probability that a randomly selected student scored between 70 and 84 ? ( round to 4 decimal places)

Sagot :

The probability that a randomly selected student scored between 70 and 84 is 0.8351

Probability

Probability is simply how likely something is to happen.

Whenever we’re unsure about the outcome of an event, we can talk about the probabilities of certain outcomes—how likely they are. The analysis of events governed by probability is called statistics.

given that:

mean = 80

standard deviation = 4

now we need to find the probability of students scored between 70 and 84

P(70<X<84) = P(X<84) - P(X>70)

                   = P(Z<(84-80)/4)-P(Z>(70-80)/4)

                   =P(Z<1) - P(Z>-2.5)

                   = 0.8413-0.0062

                   = 0.8351

the probability that a randomly selected student scored between 70 and 84 is 0.8351

To learn more about mean:

https://brainly.com/question/14127076

#SPJ4