2 out of 3
Can you find the area of a parallelogram defined by two vectors?
3 out of 3
Start with two numbers and generate a sequence where the next number is the mean of the last two numbers...
2 out of 3
Six balls are shaken. You win if at least one red ball ends in a corner. What is the probability of winning?
2 out of 3
A bus route has a total duration of 40 minutes. Every 10 minutes, two buses set out, one from each end. How many buses will one bus meet on its way from one end to the other end?
1 out of 3
Take an equilateral triangle and cut it into smaller pieces. What can you do with them?
1 out of 3
What are the possible areas of triangles drawn in a square?
2 out of 3
Which numbers cannot be written as the sum of two or more consecutive numbers?
1 out of 3
Take three whole numbers. The differences between them give you three new numbers. Find the differences between the new numbers and keep repeating this. What happens?
2 out of 3
Three children are going to buy some plants for their birthdays. They will plant them within circular paths. How could they do this?
3 out of 3
Libby Jared helped to set up NRICH and this is one of her favourite problems. It's a problem suitable for a wide age range and best tackled practically.
