In: Statistics and Probability
What are the key parameters of the distribution?
What is the Mean?
what is the Standard deviation?
Observe the given curve .It is symmetric and bell shaped.
So the distribution is NORMAL.
The curve is symmetric about 20.
So , mean = = 20
We know that almost all the observations under normal distribution lie between - 3 and +3
So, - 3 = 0 and + 3 = 40
- 3 = 0
20 - 3 = 0
20 = 3
= 20/3 = 6.6667
Standard deviation = 6.6667