Consider the density curve plotted below:
Find PX < 6.4):
Find P(X> 4.8):

Answer:
[tex] P(X<6.4)= \frac{6.4*0.2}{2}= 0.64[/tex]
[tex] P(X>4.8) =1-P(X<4.8)= 1- \frac{4.8*0.15}{2}= 1-0.36= 0.64[/tex]
Step-by-step explanation:
Part a
We want to find:
[tex] P(X<6.4)[/tex]
And we just need to find the area below the curve until x=6.4, since we have a triangle we can do this:
[tex] P(X<6.4)= \frac{6.4*0.2}{2}= 0.64[/tex]
Part b
For this case we want to find this probability:
[tex] P(X>4.8)[/tex]
And we can use the complement rule and we got:
[tex] P(X>4.8) =1-P(X<4.8)= 1- \frac{4.8*0.15}{2}= 1-0.36= 0.64[/tex]