Answer: 20%
Step-by-step explanation:
Given : Serena's father tipped a taxi driver $5 for a $25 ride.
Amount he paid for ride= $25
Amount he paid as tip = $5
Then, the percent of the tip that he paid :-
[tex]\dfrac{\text{Tip amount}}{\text{Ride fare}}\times100 \\\\=\dfrac{5}{25}\times100=20\%[/tex]
Hence, the percent of the tip that he paid = 20%