Hi!
Let's write the equation in number form first.
7 over 8
7/8
minus 1
7/8 - 1
over x
7/8 - 1/x
equals 3
7/8 - 1/x = 3
over 4
7/8 - 1/x = 3/4
Now to find the value, let's put each option as the value for x.
A. x = 1
7/8 - 1/1 = 3/4
7/8 - 1 = 3/4
0.875 - 1 = 0.75
-0.125 = 0.75
This is wrong.
B. x = 2
7/8 - 1/2 = 3/4
7/8 - 0.5 = 3/4
0.875 - 0.5 = 0.75
0.375 = 0.75
This is wrong.
C. x = 4
7/8 - 1/4 = 3/4
7/8 - 0.25 = 3/4
0.875 - 0.25 = 0.75
0.625 = 0.75
This is wrong.
D. x = 8
7/8 - 1/8 = 3/4
7/8 - 0.125 = 3/4
0.875 - 0.125 = 0.75
0.75 = 0.75
This is correct!
The answer is d. x = 8
Hope this helps! :)
-Peredhel