Library / /19 of 356

, 2007

Number theory Difficulty 1.0 Junior Find the answer Canada

In the Fibonacci sequence $1, 1, 2, 3, 5, \ldots$ , each number beginning with the 2 is the sum of the two numbers before it. For example, the next number in the sequence is $3 + 5 = 8$ . Which of the following numbers is in the sequence?

(A) $20$ (B) $21$ (C) $22$ (D) $23$ (E) $24$

Want a route through all this instead of an archive? The track puts 2,604 problems in a working order, from Junior Challenge level to the IMO shortlist.

Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.