Step-by-step explanation:
Let's take the unit ratio of weight to length:
Now that we have the unit ratio, let's multiply it to the similar pipe which is 7 feet long.
Answer:
144,003.3
a. (b) 2.5
b. (b) 1.89
E(X) =0(0.05)+1(0.25)+2(0.35)+3(0.15)+4(0.15)+5(0.15)= 2.5