the mean monthly income of trainees at a local mill is 1100 with a standard deviation of 150. find rthe probability that a trainee earns less than 900 a month g

The  probability is  

Step-by-step explanation:

From the question we are told that

   The sample mean is  

    The  standard deviation is  

     The random number value is  x =900

The probability that a trainee earn less than 900 a month is mathematically represented as

Generally the z-value for the normal distribution is mathematically represented as

So From above we have

Now from the z-table

answer: 21$

step-by-step explanation:

$42 / $14 = 3   (ratio 3: 1)

$7 x 3 = $21