Answer:
The correct option is (b).
Step-by-step explanation:
If X
N (µ, σ²), then
, is a standard normal variate with mean, E (Z) = 0 and Var (Z) = 1. That is, Z
N (0, 1).
The distribution of these z-variate is known as the standard normal distribution.
The mean and standard deviation of the active minutes of students is:
<em>μ</em> = 60 minutes
<em>σ </em> = 12 minutes
Compute the <em>z</em>-score for the student being active 48 minutes as follows:

Thus, the <em>z</em>-score for the student being active 48 minutes is -1.0.
The correct option is (b).
The answer is a rational number is one integer divided by
another, and can be represented in either decimal of fraction form. The explanation
behind this is visualize you are using long division to divide one number by one
more. You divide, and then you acquire a remainder. Then you carry down a
zero (multiply by ten) and divide again. Well, there are only so many balances
you could perhaps have. For example, for 5, your choices are 0, 1, 2, 3,
and 4. Sooner or later, you will replicate a remainder, at which fact you
will just keep dividing the same method you did last time you saw that
remainder -- and that's the reason why it repeats.