Question Detail
Question
A GP has first term 5 and common ratio 2. Find the sum of the first 10 terms.
Correct Answer
Option A is the correct answer.
Detailed Explanation
S_n = a(r^n−1)/(r−1) = 5(2^10−1)/(2−1) = 5(1024−1) = 5×1023 = 5115.
Hint
Use S_n = a(r^n−1)/(r−1) for r>1.