Question

An assignment  produced grades with a mean of 79.2 and a standard deviation of 11.9.

(a) Find the z-score for each value of x = 60. (Give your answer correct to two decimal places.) (b) Find the z-score for each value of x = 72. (Give your answer correct to two decimal places.) (c) Find the z-score for each value of x = 89. (Give your answer correct to two decimal places.) (d) Find the z-score for each value of x = 97. (Give your answer correct to two decimal places.)

Answer 1

We are given that an assignment produced grades with mean, μ = 79.2 and standard deviation, σ = 11.9.

We need to find the z-score corresponding to different grades (x-values), for this purpose, we use the following formula for the z-score:

(a)

The z-score for the value of x = 60 is given by:

(b)

The z-score for the value of x = 72 is given by:

(c)

The z-score for the value of x = 89 is given by:

(d)

The z-score for the value of x = 97 is given by:

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