The amount of time that customers wait in line during peak hours at one bank is normally distributed with a mean of 13 minutes and a standar

Question

The amount of time that customers wait in line during peak hours at one bank is normally distributed with a mean of 13 minutes and a standard deviation of 3 minutes. The percentage of time that the waiting time lies between 11 and 13 minutes is equal to the area under the standard normal curve between ___ and ___.

in progress 0
Adalynn 1 week 2021-10-11T12:12:00+00:00 1 Answer 0

Answers ( )

    0
    2021-10-11T12:13:19+00:00

    Answer:

    It is between -067 and 0.

    Step-by-step explanation:

    In order to do the calculation, we employ the formula z score because random variables are standardized into z scores. Another name for the z score is standard score and its formula is as given below:

    P(L ≤ x ≤ H) = P{[(L – H) ÷ SD] ≤ z ≤ [(H – H) ÷ SD]} ………… (1)

    P = probability notation

    L = Lower number = 11

    H = Higher number = 13

    SD = Standard deviation = 3

    Substituting the above values into equation (1), we will obtain:

    P(11 ≤ x ≤ 13) = P{[(11 – 13) ÷ 3] ≤ z ≤ [(13 – 13) ÷ 3]}

                        = P{[(-2) ÷ 3] ≤ z ≤ [0 ÷ 3]}

                        = P{-0.67 ≤ z ≤ 0}

    Therefore, the percentage of time that the waiting time lies between 11 and 13 minutes is between -067 and 0 under the standard normal curve area.

Leave an answer

45:7+7-4:2-5:5*4+35:2 =? ( )