Respuesta :
Answer:
45 minutes
Step-by-step explanation:
I am assuming you could add the times (60 + 30) and divide it by two because there are two girls (90 / 2) and that would give you the average time.
Answer: 45 minutes, because that is the half way point through the two, because one will speed up the other and one with slow down the other.
Step-by-step explanation: