The real numbers 7, a, b, c, d, 7/32 form a geometric progression. What is b?
In a geometric progression: n1 = 7 and n6 = 7/32
Since n6 = n1 · r5 ---> 7/32 = 7 · r5
---> 1/32 = r5 (divide by 7)
---> 1/2 = r (take the fifth root)
a = 7 · (1/2)
b = 7 · (1/2)2
