Not sure about the first one,
The second one is 1/9.
3*60 = 180 minutes
80/180 = 0.44
1-0.44 = 0.56
it was a 56% decrease in commute time
You would get a total of you count them by pairing them up. The combos are as follows:
For your answer you can count a total
1,5
1,4
1,3
1,2
2,3
2,4
2,5
3,4
3,5
4,5
