She has paid for 11 rides.
She started with 50 dollars and at the end she has 6 dollars left. Each ride costs 4 dollars. The follow equation could be created:
$6 = $50 - $4r
Six dollars remaining = original fifty dollars - four dollars per ride.
The number of rides is represented by the variable r.
To solve:
$6 = $50 - $4r
Subtract 50 from both sides
-$44 = -$4r.
Divide each side by -4 to get the number of rides (r)
11 = r
Therefore, she has paid for 11 rides.
