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A Problem of Time

Age 14 to 16
Challenge Level Yellow starYellow starYellow star
Secondary curriculum
  • Problem
  • Student Solutions

"It was the best butter," the March Hare meekly replied.
"Yes, but some crumbs must have got in as well," the Hatter grumbled: "you shouldn't have put it in with the bread-knife."
The March Hare took the watch and looked at it gloomily: then he dipped it into his cup of tea, and looked at it again: but he could think of nothing better to say than his first remark, "It was the best butter, you know."


Tea Party

Consider a watch face which has all the hours shown by the same mark, and both hands the same in length and shape. It is opposite to a mirror. Find the time between 6 and 7 when the time as read direct and in the mirror is exactly the same.


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A Method of Defining Coefficients in the Equations of Chemical Reactions

A simple method of defining the coefficients in the equations of chemical reactions with the help of a system of linear algebraic equations.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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