When working on mathematical tasks, you may sometimes discover unexpected results that take you by surprise. In this feature, we have chosen some problems that we hope will astonish and amaze you.
problem
Favourite
Subtraction Surprise
Age
7 to 14
Challenge level
Try out some calculations. Are you surprised by the results?
problem
Favourite
Legs Eleven
Age
11 to 14
Challenge level
Take any four digit number. Move the first digit to the end and move the rest along. Now add your two numbers. Did you get a multiple of 11?
problem
Favourite
Angles inside
Age
11 to 14
Challenge level
Draw some angles inside a rectangle. What do you notice? Can you prove it?
problem
Favourite
Triangle in a Triangle
Age
14 to 16
Challenge level
Can you work out the fraction of the original triangle that is covered by the inner triangle?
problem
Favourite
Areas and Ratios
Age
16 to 18
Challenge level
Do you have enough information to work out the area of the shaded quadrilateral?
problem
Another Triangle in a Triangle
Age
16 to 18
Challenge level
Can you work out the fraction of the original triangle that is covered by the green triangle?
