Answer:
[tex]P(X>3)P(X>4)=(1-F_1(3))(1-F_2(4))[/tex]
Step-by-step explanation:
We require more information by I will explain in principle:
If Type A has at least 300 hours and Type B at least 400 hours.
[tex](X>3)(Y>4)=P(X>3)P(X>4)[/tex]
You need to determine the Probability density function of X and Y and then subtract 1 from both
[tex]P(X>3)P(X>4)=(1-F_1(3))(1-F_2(4))[/tex]
This will give you the probability of the expression.