I’m trying to help my kid with his homework. I thought I was good at statistics, but it turns out I am not. Or at least, I can’t figure out the right numbers to use in the formulas. Can someone spot check at least my initial logic? I feel the question is worded in a very weird way.

I want to say that there are 84 E jobs, 16 L jobs, and 14 (rounded) P+L jobs. Is that correct?

Original question:

84% of a contractors jobs involves electrical work. 75% of a contractors jobs involve plumbing work. Of the jobs that involve plumbing, 90% of the jobs also involves electrical work.

Let E = jobs involving electrical work

L = jobs involving plumbing work

Suppose one of the contractors jobs is randomly selected.

Using the sixth Excel worksheet,

a) Find P(E).

b) Find P(L).

c) In words, what is P(E | L).

d) Find P(E | L).

e) Find P(E and L).

f) Are E and L independent events? Why or why not?

g) Find P(E or L).

h) Are E and L mutually exclusive? Why or why not?

Someone please help. Never been so glad to be out of school in my life.