Answer:
20%
Step-by-step explanation:
Given that,
In a survey of 3,100 people who owned a certain type of​ car, 620 said they would buy that type of car again.
It means there are 620 people surveyed who were satisfied with the​ car.
Required percentage is given by :
[tex]\%=\dfrac{620}{3100}\times 100\\\\\%=20\%[/tex]
So, the required percentage is 20%.