Library / /89 of 165

, 2019

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

Megan writes down a list of five numbers. The mean of her first three numbers is $-3$ . The mean of her first four numbers is $4$ . The mean of her first five numbers is $-5$ . What is the difference between her fourth number and her fifth number?

(A) $66$ (B) $55$ (C) $44$ (D) $33$ (E) $22$

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: UK Mathematics Trust, licensed © UK Mathematics Trust; past papers published free at ukmt.org.uk. Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.