Ok, I am about 2 minutes away from losing my sanity! I am taking a statistics class and was doing fairly well until now. I ran up to the bookstore and picked up Cliffs Notes for Statistics and I still can't figure out this problem. If I can figure it out and know how to come up with the answer, I would be able to work out the rest of the problems since they are similar... If anyone's bored feel free to try it out

"In how many orders can three broken computers and two broken printers be repaired if (a) there are no restrictions, (b) the printer must be repaired first, (c) the computers must be repaired first? (d) If the order of repairs has no restrictions and the order of repairs is done at random, what is the probability that a printer will be repaired first?

I have the answers and know how to get them for a,b,&c. But d I just can not figure out. I have the answer out of the back of the book it is 0.1 but I need to know how to work it out

Oh and in case anyone is interested the answers are:

a. 120

b. 12

c. 12

d. 0.1

"In how many orders can three broken computers and two broken printers be repaired if (a) there are no restrictions, (b) the printer must be repaired first, (c) the computers must be repaired first? (d) If the order of repairs has no restrictions and the order of repairs is done at random, what is the probability that a printer will be repaired first?

I have the answers and know how to get them for a,b,&c. But d I just can not figure out. I have the answer out of the back of the book it is 0.1 but I need to know how to work it out

Oh and in case anyone is interested the answers are:

a. 120

b. 12

c. 12

d. 0.1