Question #c856b

2 Answers
Apr 16, 2017

Answer:

There are 16 windows on the first floor.

Explanation:

Let #x# equal the number of windows on the second floor.

Thus, the number of windows on the first floor is equal to #x-2#, and the number of windows on the third floor is #x/2#.

Given that there are 9 windows on the third floor, we set #x/2# equal to 9 and find that:
#x/2=9#
#x=18#

There are thus 18 windows on the second floor, but there are two fewer on the first floor. Therefore the first floor has 16 windows.

Apr 16, 2017

Answer:

#16# windows on the first floor.

Explanation:

We have to define a variable first to be able to make an equation.

The first floor has the smallest number of windows, so,
let the number of first floor windows be #x#.

Write the windows on the other floors in terms of #x#

The second floor has two more: #" ":.x+2# windows

The third floor has half as many as the second floor:

The number of windows on the the third floor = #(x+2)/2#

But there are #9# windows on the third floor.
#:. (x+2)/2 = 9" "larr# solve for x

#x+2 = 2xx9#

#x =18-2#

#x = 16#

#16# windows on the first floor.