Question

~RATIOS~ -Please help with the following picture :)

Answer 1

This is what I know:
$300:6$ (first day)
$250:5$ (second day)
$?:3$ (Third day)
To get the unit rate, divide the first ratio(300 by 6), which is 50.
The unit rate is 50
Then: Multiply the unit rate by 3. 
$50*3=150$
Therefore, Evan's family drove 150 miles in 3 hours

Answer 2

Simple, they're driving 50 miles per hour. So the final day, they drove 150 miles.