Answer:
There are _18_ windows for every 3 penguins.
There are _6_ windows for every 1 penguin.
Explanation:
Since its is already given that 3 penguins = 18 windows, the first blank is 18
To get number of windows for 1 penguin, we divide 18 by 3, so:

Hence, second blank is 6 windows for every 1 penguin.