What is the 8th term in the standard Fibonacci sequence: 1, 1, 2, 3, 5, 8, 13, ...?
Answer and explanation
Correct answer: B. 21
- Step 1: In the Fibonacci sequence, each term is the sum of the preceding two terms: F_n = F_(n-1) + F_(n-2). Step 2. The 7th term is 13 and 6th term is 8. The 8th term = 13 + 8 = 21. Answer: 21. Why not the others: 20 adds 7 to 13; 19 adds 6 to 13; 24 erroneously calculates 13 + 11 instead of 13 + 8.
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