Answer: 12 for the main square
Explanation:
take the 4 and the 3 and multiply it, makes 12. you see how each stair is 6 inches and there is 3 full steps which makes it 1.50 feet. 12 x 1.50 is 18. that makes your main square. I'm sorry but I cant really help you with the steps but that was also confusing to me.