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IKMC 2023 - Grades 11-12 - Self-study Question 13

IKMC · IKMC 2023 - Grades 11-12 - Self-study

Question 13

Five numbers $a_1,a_2,a_3,a_4,a_5$ have sum S and satisfy $a_k=k+S$ for $1\le k\le5$. Find S.
  1. $15/4$
  2. $-15/4$
  3. $-15$
  4. 15
  5. Another number