I don't know the formula to figure this out.
Charlie and Peter are driving around a racetrack. Charlie drives at an average speed of 108 miles per hour. Peter drives at an average speed of 99 miles per hour. Peter is given a head start of 12 miles. Charlie and Peter finish at the same time. How far does Charlie drive?
126,132,144 or 156 miles
Peter drives 12 miles less than Charlie.
they both drive the same time
so, if Charlie drives c miles,
and since time = distance/speed,
c/108 = (c-12)/99
99c = 108(c-12)
9c = 1296
c = 144 miles
To find out how far Charlie drives, we need to consider the time it takes for both Charlie and Peter to complete the race. Since they finish at the same time, their race times must be equal.
Let's denote the distance Charlie drives as 'x' miles. To find 'x', we can set up an equation based on the formula:
distance = speed * time
For Charlie:
x = 108 * time (since Charlie drives at an average speed of 108 miles per hour)
For Peter:
x - 12 = 99 * time (since Peter is given a head start of 12 miles and drives at an average speed of 99 miles per hour)
Since both Charlie and Peter finish at the same time, we can set these two equations equal to each other:
108 * time = 99 * time + 12
Simplifying the equation:
9 * time = 12
Dividing both sides by 9:
time = 12 / 9 = 1.33 hours
Now that we have the time, we can substitute it back into one of the earlier equations to find 'x', the distance Charlie drives:
x = 108 * 1.33
x = 143.64 miles
Therefore, Charlie drives approximately 143.64 miles.