Negative number cards

Overview

Using this Resource

Connecting to the Curriculum

Marking Student Responses

Working with Students

Further Resources

This task is about multiplying negative numbers.

Six students are each given a card with a number on it as shown above.

The students get into pairs, and each pair multiply their numbers together to get a score.

Question 2Change answer

a) What score would the following pairs get when they multiply their numbers together?

i) Chris and Sue

ii) Anne and Paulette

iii) Marie and Chris

iv) Paulette and Marie

b) Which pair (of all possible pairs) of students could multiply their numbers together to make:

i) the biggest score? and

ii) the most negative score? and

Task administration:

This task can be administered with pencil and paper or online.

Level:

Curriculum info:

Keywords:

Description of task:

Students solve multiplication problems involving negative numbers, finding the biggest and the smallest products.

Answers/responses:

			Y10 (11/2001)
a)	i) ii) iii) iv)	8 ⁻21 ⁻20 15	4 correct - very easy 3 correct - very easy
b)	i) ii)	Marie and Brian [accept ⁻5 and ⁻6] Anne and Brian [accept 7 and ⁻6]	moderate moderate

Diagnostic and formative information:

	Common error	Likely reason
b) i)	Anne + Chris	Fails to see that ⁻5 × ⁻6 is greater than 7 × 4, probably because they see the former as negative.

Next steps:

Extension:
The students then get into groups of three and again multiply their numbers together to get a score.

Which group of three could make the smallest score?

_______________ and _______________ and _______________