Find two geometric means between 7 and 875.

Inserting two geometric means between the numbers would make a geometric sequence with first term equal to 7 and fourth term equal to 875. To find the common ratio, use the equation,
                                   an = a1 x r^(n - 1)
Substituting the values, 
                                    875 = (7) x r ^(4 - 1) 
The value of r is 5. Thus, the two geometric means are 35 and 175. 

Two because two of one thing is two.