7, _, 175, 875. Find the geometric mean between 7 and 175.
Formula
Use t3 = 175 = tn
With that use n=3
tn= t1 (r^n-1)
175 = 7 (r^3-1)
175= 7 (r^2)
*transposition*
175/7 = r^2
25= r^2
*the square root of both sides*
r = 5
So...
tn = t1 (r^n-1)
t2= t1 (r^2-1)
t2= t1 (r^1)
t2= 7 (5)
t2 = 35
Therefore, the geometric mean between 7 and 175 is 35.
