Step 1 :Calculate the discounted price per 40 miles for Taxi A: \(45 - 0.15 \times 45 = 38.25\)
Step 2 :Find the cost per mile for Taxi A: \(\frac{38.25}{40} = 0.95625\)
Step 3 :Calculate the total cost for Taxi A for 240 miles: \(0.95625 \times 240 = 229.5\)
Step 4 :Calculate the total cost for Taxi B for 240 miles: \(0.9 \times 240 = 216\)
Step 5 :\boxed{216}