Answer:
The brother is likely wrong.
Step-by-step explanation:
The range of the vehicle with a full tank is ...
(13.5 gal/tank)(25 mi/gal) = 337.5 mi/tank
You have 1/4 tank, so your range is ...
(337.5 mi/tank)(1/4 tank) = 84.375 mi
If you make the 85 mile distance, it will be because you achieved gas mileage better than average and/or your gas gauge gives you some cushion.
Unit analysis says you do not have the necessary range.