The answer would be 80. I'm pretty sure. You would multiply the money amount and how much she bought.
Since the first car travels 55 miles per hour and starts an hour early, by 4:00 it is 55 miles away from the other car. Therefore, the equation is 55+a(some value)+b(another value)=380. If a car travels 55 miles per hour, that means that we add 55 for each hour and 55*x (if x is the number of hours) is the distance traveled. We have accounted for the first hour, so this is similar to saying that they start 55 miles away at 4:00 and go from there. For the other car, since it travels 75 miles per hour, its distance in hours is 75*x (the amount of time spent should be the same if we start at 4:00). Therefore, since they travel away from each other, our total distance is 55+55x+75x=380. Subtracting 55 from both sides (and combining like terms), we get 130x=325. Next, we divide both sides by 130 to get 2.5 hours, or 2 hours and 30 minutes
hope that helps
The square root rounded would be 4.9 if you want a whole number try 5. Since twenty four does not have a square root it is hard to tell.
B, because 12 inches equals one foot so it's one foot a minute. In an hour it would walk 60 feet as to A would only walk 52