Answer:
340 boats
---------------
3/4 hours
Explanation:
Since we are asked to find the unit rate per hour, we must convert the minutes given into hours.
45 minutes⋅ 1 hour / 60 minutes = 3/4 hours
Now, we simply put the number of toy boats given in the problem over the total amount of time (in hours) required to paint them. Thus, our final answer is:
340 boats
------------
3/4 hours
