What is the sum of the infinite geometric series 1 + 1/3 + 1/9 + 1/27 + ... ?
Correct: E
The sum of an infinite geometric series with first term a and common ratio r (where |r| < 1) is given by S = a / (1 - r). In this case, a = 1 and r = 1/3. Therefore, S = 1 / (1 - 1/3) = 1 / (2/3) = 3/2.