Problem 121

We can express the number of inches of rain in a ratio, $\frac{366 \text{ inches}}{1\text{ month}}$. We need to find to find the number of hours, but first we need to find the number of days. We know there are 31 days in July, so we get $$\frac{366 \text{ inches}}{1 \text{ month}} \times \frac{1 \text{ month}}{31 \text{ days}}$$
We know there are 24 hours in a day, so we get $$\frac{366 \text{ inches}}{1 \text{ month}} \times \frac{1 \text{ month}}{31 \text{ days}} \times \frac{1 \text{ day}}{24 \text{ hours}}$$
And simplifying gets us $\dfrac{366 \text{ inches}}{31 \times 24 \text{ hours}}$, which is $\boxed{\text{A}}$.
Note that in the simplifying step, we noted that the month and day units cancel, leaving us with only inches per hour.