2026 · Q40
The numbers 59, 53, 51, 43, 36, (8x + 1), (x^2 + 1), 13, 12, 9, 7, 3 are written in descending order and their median is 25. What is/are the values of x?
Elementary MathematicsStatistics
- A-12 only
- B4 only
- C-12, 4
- D12, -4
Explanation
For 12 numbers the median is the mean of the 6th and 7th terms: (8x+1)+(x²+1)=50, i.e. x²+8x−48=0, giving x=4 or x=−12. But x=−12 would make the 6th term 145, destroying the descending order, so only x=4 is admissible, option B.