**This activity uses a program that generates a pair of numbers, along with their the sum, difference, product and quotient.**The teacher can choose to display or hide these numbers providing a rich source of challenges.

The activity addresses the following objectives.

Year 7:

- Understand and use the rules of arithmetic and inverse operations in the context of positive integers
- Recall number facts, including positive integer complements to 100 and multiplication facts to 10 × 10, and quickly derive associated division facts

- Use known facts to derive unknown facts

- Solve a pair of simultaneous linear equations by eliminating one variable

- Factorise quadratic expressions, including the difference of two squares
- Solve quadratic equations by factorisation

- As a starter for less able pupils. The two numbers are displayed and the challenge is to calculate sum, product and differences
- To support the teaching of factors. The product is displayed and the groups challenged to generate possible factors
- As a starter to find the original numbers by revealing sum, product, difference and quotient one at a time.
- To help pupils make links to factorising quadratics

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