Admission to a certain university is determined by an entry exam. The scores of this test are Normally distributed with a mean of 400 and a

Question

Admission to a certain university is determined by an entry exam. The scores of this test are Normally distributed with a mean of 400 and a standard deviation of 60. Only students who score in the top 30% will be offered admission. Amy scores 425 on the test. Choose the most accurate statement? A) The top 30% is defined with a score less than or equal to 431.4 so she will be admitted. B) The top 30% of all students have scores greater than or equal to 520 so she will not be admitted. C) The top 30% of all students have scores greater than or equal to 460 so she will not be admitted. D) The top 30% is defined with a score greater than or equal to 431.4 so she will not be admitted.

in progress 0
Ella 3 weeks 2021-11-17T14:40:39+00:00 1 Answer 0 views 0

Answers ( )

    0
    2021-11-17T14:41:44+00:00

    Answer:

    The top 30% is defined with a score greater than or equal to 431.44 so she will not be admitted (D)

    Step-by-step explanation:

    Mean m = 400

    Standard deviation S = 60

    Firstly, we have to determine the cut off mark,

    Since Only students who score in the top 30% are accepted, the cut off mark can be determined from 70% of the mark.

    P(cut off mark = X) = Z[( X -m)/S) <x]

    =ยข(X-400/60) = 0.7

    From Normal distribution table,

    X-400/60 = 0.524

    X = 431.44

    Therefore, the cut off mark is 431.44

    Since Amy scores 425 on the test.

    Therefore, The top 30% is defined with a score greater than or equal to 431.44 so she will not be admitted (D)

Leave an answer

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