Review on Normal Distribution

What is the total area under the standard distribution curve?

• 100

• 50

• 0.5

• 1

What is the shape of the normal curve

• half curve

• bell curve

• round curve

• square curve

The normal curve is symmetrical about the mean

• true

• false

What is NOT true about the standard normal distribution?

• It is bell-shaped.

• The mean is 0 and standard deviation is 1.

• It is asymmetrical.

• It can be used to model any normal distribution.

A normal distribution is a continuous random variable.

• true

• false

We CANNOT use normal distribution to approximate a binomial distribution.

• true

• false

What do we need to do FIRST before using normal to approximate a binomial distribution?

• standardization

• checking np>5, nq>5

• draw standrd normal bell curve

• continuity correction

Any normal distribution can be transformed into a standard distribution.

• true

• false

Answer explanation

Through the process of standardization.

With reference to the diagram, what is the probability of P(Z<0)?

• 0.45

• 0.5

• 1

• 0.55

Given that P(Z>a)=0.8. Where does a located on the x-axis ( number line)?