A geometric sequence has first term 1 and common ratio 3. Find the sum of the first 5 terms.
Answer and explanation
Correct answer: C. 121
- Step 1: .
- Step 2: .
Answer
121.
Why not the others: 243: that is the th term. 242: it forgets to divide by . 81: that is the last term.
Practise more Sequences.
Free questions with an explanation for every one, and full timed Sultan Qaboos University Foundation & Aptitude Test mock tests.
More Sequences questions
- An arithmetic sequence has first term 1 and common difference 3. Find the sum of the first 17 terms.
- An arithmetic sequence has first term 2 and common difference 3. Find the sum of the first 25 terms.
- An arithmetic sequence has first term 7 and common difference 3. Find the sum of the first 23 terms.
- An arithmetic sequence has first term 2 and common difference 4. Find the sum of the first 15 terms.
- In an arithmetic sequence the first term is 3 and the 14th term is 55. Find the common difference.
- In an arithmetic sequence the first term is 6 and the 16th term is 81. Find the common difference.