#### Answer

About $70$ more dollars are needed for the trip.

#### Work Step by Step

The cost of gas at 47 dollars can be estimated to 50 dollars. THE food costs of 311 dollars can be estimated to 300 dollars. and the hotel cost of 405 dollars can be estimated to 400 dollars. If we add our estimates: 50 + 300 + 400, we get 750 dollars.
Then, 681.79 is taken from savings. This may be estimated to 680 dollars. Th difference between the cost estimate and the 680 is 70 dollars. SO, the person needs about 70 more dollars for the trip.