Make a conjecture about the sum of the squares of the odd positive integers. Can you prove it?
Summing Geometric Progressions
Age 14 to 18 Challenge Level
Aswaath, from Garden International School, Kuala Lumpur, adapted Alison's method and then used a spreadsheet to calculate the sums directly to verify that Alison's method worked.
Well done to Matthew from Westlakes Academy, Andrew from West Island School, Hong Kong, Michael, and Irina from Loughborough High School for their correct solutions. You can readMichael's solution and Irina's solution.
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embed rich mathematical tasks into everyday classroom practice.