Answer
The probability that the randomly chosen student’s score is between 20 and 30 is 0.6.
Work Step by Step
Here, we have n = 25, μ = 25, x̅ = 20, σ = 6.5
We need to calculate z score for the probability:
$z = \frac{x - μ}{σ} = \frac{20-25}{6.5} = -0.769$
$z = \frac{x - μ}{σ} = \frac{30-25}{6.5} = 0.769$
Using Table A of the book, we have:
P(-0.769 < z < 0.769) = 0.5588
