If the two floors in a certain building are 9 feet apart, how many ste

Hello sinhap07
Even if stairs in circular pattern they are still should going to the next floor. Right?
So your style of thinking change nothing in this task.

Statement 1 tells us the height of each stair step - 3/4 foot and vertical distance between 2 floors is 9 feet, it is sufficient to find the number of steps 9/ (3/4)= 12 steps Sufficient
Statement 2 gives us the width of each step which is totally unnecessary in calculating the number of steps insufficient
correct answer - A

Let's sketch a diagram of the stairs. Keep in mind that we don’t know the number of stairs between the floors, but the problem will be easier to solve by first drawing a picture.



From the picture, we can see that if we knew the height of each stair, we could determine the number of stairs that exist between floor one and floor two. Creating an equation we have:

9 feet/(height per step) = number of steps between floors

Statement One Alone:

Each step is 3/4 foot high.

Using the information in statement one we can determine that there are 9/(3/4) = 12 steps between floor 1 and floor 2. Statement one is sufficient to answer the question. We can eliminate answer choices B, C, and E.

Statement Two Alone:

Each step is 1 foot wide.

Knowing only the width of each step does not provide enough information to answer the question.

Answer: A

Scott brilliantly explained. Thanks

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