Kate rode her bicycle to visit her grandmother. The trip to Kate’s grandmother’s house was mostly uphill, and took m minutes. On the way home, Kate rode mostly downhill and was able to travel at an average speed twice that of her trip to her grandmother’s house. Which of the following expresses the total number of minutes that Kate bicycled on her entire trip?

F. 3m
G. 2m
H. m + 1/2
J. 3m/2
K. m/2