Numeracy, Maths and Statistics - Academic Skills Kit

Positive and Negative Numbers (Business)

ContentsToggle Main Menu 1 Introduction 2 Worked Example 3 See Also

Introduction

Positive numbers are those which are greater than zero. Negative numbers are those which are less than zero. Below is a table to help you remember what to do with the sign when using multiplication or division and addition or subtraction.

\begin{array}{ccccc} \text{Positive} & \times / \div & \text{Positive} & = & \text{Positive} \\ \text{Negative} & \times / \div & \text{Negative} & = & \text{Positive} \\ \text{Positive} & \times / \div & \text{Negative} & = & \text{Negative} \\ \text{Negative} & \times / \div & \text{Positive} & = & \text{Negative} \\ \end{array}

\begin{array}{ccccc} + (-\text{Number}) &= -\text{Number} \\ - (+\text{Number}) &= -\text{Number} \\ + (+\text{Number}) &= +\text{Number} \\ - (-\text{Number}) &= +\text{Number} \\ \end{array}

For more information see positive and negative numbers in our Numeracy section.

Worked Example

You are making losses at your company. In January you make $-£3000$, in February you make $-£2980$, and in March you make $£1298$. In April you make one third of the loss you made in January, in May you make half as much as in March and in June you make $£0.00$.

How much of a loss have you made in the half of the year?

Solution

This is a calculation involving both positive and negative numbers.

Firstly, calculate how much profit you made in April and May.

In April you made one third of the loss you made in January so you need to divide $-£3000$ by 3. This gives

$$-£3000 \div 3 = -£1000$$

In May you made half as much as in March. This gives

$$1298\div2 = £649$$

Now total all of these loss values up:

\begin{align} \text{Total profit} &= \text{Profit in Jan} + \text{Profit in Feb} + \text{Profit in Mar} + \text{Profit in Apr} + \text{Profit in May} + \text{Profit in Jun}\\ &=(- £3000) + (- £ 2980) + £1298 + (- £1000) + £649 + £0\\ &= - £ 5033 \end{align}

Your company has made a loss of £$5033$ in the first half of the year.