There used to be a popular word definition game on TV called Call My Bluff. The aim was for two teams of three to take it in turns to provide three definitions of an arcane word, only one of which was correct. The other team had to guess the correct definition, the other two being bluffs. Here's how to play mathematical Call My Bluff.
Divide the class into teams of four and arm them with maths dictionaries. Each team selects a word, writing one correct definition and three false versions.
The aim of the game is to make all versions sound as credible as possible.
A group at a time can then present their definitions to the class, who listen and consult each other before deciding who might be right. They write their answers on a record sheet. After every team has had a go, the record sheets are collected and each team supplies their answer.
DING! And the word is numerator.
1. A numerator is a number which is not a prime number.
2. A numerator is the top digit in a fraction.
3. A numerator is the number occurring most often in a set of data.
4. A numerator is an early sort of counting frame like an abacus
John Dabell is a teacher trainer and maths consultant