Posted by Julie on .
A random variable N has a cumulative distribution function given by
F(x)={ 0 for x<1
0.2 for 1<=x<2
0.5 for 2<=x<3
0.8 for 3<=x<4
1 for 4<=x
Find the mean of N.

PLZZZ I NEED HELPP 
Julie,
can I please have some1 help me with this problem