We have that an inverse variation in a function is given by:

We must find the value of the constant k.
To do this, we substitute the values of x1 = 12, y1 = 15.
We have then:

Clearing k we have:

Substituting the value of k we have that the inverse variation is:

For y2 = 3 we have:

Clearing x2 we have:
Answer:
Me being a junior in high school and not knowing middle school math
11:00 P.M.
Bus A would do the route 13 times
Bus B would do the route 12 times