Question

Help normal distributions

Answer 1

Answer:

0.0215

Step-by-step explanation:

The average weekly wage is $400 and the standard deviation is:

$50

The z-score for $250 is given by:

$z = \frac{x - \mu}{ \sigma}$

Plug in the values to get:

$z = \frac{250 - 400}{ 50} = - 3$

The z-score of $300 is

$z = \frac{300 - 400}{ 50} = - 2$

The probability of earning less than:

$250 is

P(X<250)=0.0013, we got this by reading -3 under zero on the standard normal distribution table.

Similarly:

P(X<300)=0.0228

P(250<X<300)=0.0228-0.0013=0.0215

Therefore the probability that a workeep makes between 250 and 300 dollars is 2.15%