Increasing the amount of fuel by 28 gallons from 10 to 38 increased the weight by 154 pounds from 2155 to 2309 pounds.
The increase to 52 gallons of fuel is an increase of 14 gallons from 38, which is half the previous increase of 28 gallons. Thus, we expect the increase in weight from 2309 pounds to be half the previous increase, or 154/2 = 77 pounds.
2309 + 77 = 2386 . . . pounds
We expect the airplane to weigh 2386 pounds when it is carrying 52 gallons of fuel.