Sum & product
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
Year 9:
• Use known facts to derive unknown facts
Year 10:
• Solve a pair of simultaneous linear equations by eliminating one variable
Year 11:
• Factorise quadratic expressions, including the difference of two squares
• Solve quadratic equations by factorisation
Some suggested contexts that the activity might be used to support:
• 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.