Answer:
I think 478.4 ._.
Explanation:
First, find out how many gallons of gasoline she can buy with $18.50 by dividing 18.50 by 1.25 to get 14.8 gallons. Then, since he already has 6 gallons in his tank, add 6 to 14.8 = 20.8. Finally multiply this by the ratio of gallons to miles (23) to get 478.4