Answer: Blll's family has 70% of driving left.
Explanation:
The total mileage of the trip = 3,000 miles.
miles driven so far = 900miles
Miles of diatance left = 3000- 900=2100
Percentage of driving left = Miles of diatance left / Total miles to cover x 100
=2100/3000 x 100
= 7/10 x100
70%