For number 1:
If a month has 20 work days at 8 dollars per day, that would mean 160 dollars per month. The pass is 80 dollars so you do 160 - 80 to find that you would save 80 dollars with the pass, option A.
For number 2:
Same process. 5 days in a work week, 4.25 per day is 21.25 per week. Pass is 19.75 so you do 21.25 - 19.75 to find that you would save 1.50 with the pass, option C.
For number 3:
16 days a month at 6.30 a day is 100.80 per month. Pass is 78; 100.80 - 78 = 22.80, option D.
For number 4:
12 times a month at 4.50 is 54. Monthly is 58. So it would be more efficient to pay daily, option A.
