A hint to get started
Count a shared middle pearl once
A string has 31 pearls, with the largest and most expensive in the middle. From one end each pearl is worth $100 more than its predecessor up to the middle; from the other end each is worth $150 more. The whole string costs $63,000. Find the middle pearl’s value.
[2007/SAJC/I/9(a)]
CJC · Discussion · Question 5
Each inclusive half has sixteen pearls, but the full string has thirty-one.