Question

1. An event has a 0.1230 probability of occurring. State as z score and
   SELECT ALL THAT APPLY

   	a.	1.16
   	b.	-1.16
   	c.	1.6 standard deviations above the meen
   	d.	1.6 standard deviations below the mean

Answer 1

The answer is:

We are dealing with the standard normal distribution, with parameters:

We need to find a z-score z so that the corresponding cumulative normal probability is equal to 0.123. Mathematically, z is such that:

The corresponding z score so that the cumulative standard normal probability distribution is 0.123 is

None of the other options are correct. This z score is basically 1.16 standard deviations below the mean, NOT 1.6 deviations below the mean.

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