Answer: 6.125 hour
Explanation:
Train 1 ===> 1 hour = 90 miles
Train 2 ===> 1 hour = 120 miles
1 hour = 90 + 120 = 210 miles apart
210 miles = 1 hour
735 miles = 735 ÷ 210 = 6.125 hours
simple first we find the miles per gallon
so 300/15=20 therefor he would only need a extra 3 gallons to go 360 miles so your answer is
B.18