Answer:

1. 80 × 15.25 = 1220

80 - 3 = 77 × 20 = 1540

amount of gain = 1540 - 1220 = 320

2. cost of adult tickets = 25.75 × 3 = 77.25

cost of student tickets = 15.75 × 4 = 63

total cost = 77.25 + 63 = 140.25

3. total amount = 8(45.55) + 4(45.55×2.5)

total amount = 819. 9 ≈ 820

4. Total km = 8.75 × 6 = 52.5 km

5. Carol Time = 0.75 - (0.75×0.25) = 0.5625 hour

my answer is base on my interpretation on the problems.