Everyday maths 2 (Wales)
Everyday maths 2 (Wales)

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

5 Negative numbers

Negative numbers come into play in two main areas of life: money and temperature. Watch the animations below for some examples.

Download this video clip.Video player: bltl_1_3_negative.mp4
Copy this transcript to the clipboard
Print this transcript
Show transcript|Hide transcript
 
Interactive feature not available in single page view (see it in standard view).

Activity 11: Negative and positive temperature

  1. The table below shows the temperatures of cities around the world on a given day

Table 5
LondonOsloNew YorkKrakówDelhi
4˚C−12C7˚C−3˚C19˚C
  •  

    • a.Which city was the warmest?

    • b.Which city was the coldest?

    • c.What is the difference in temperature between the warmest and coldest cities?

Answer

  1.  

    • a.Delhi was the warmest city as it has the highest positive temperature.

    • b.Oslo was the coldest city as it has the largest negative temperature.

    • c.The difference between the temperatures in these cities is 31˚C.

      From 19˚C down to 0˚C is 19˚C and then you need to go down a further 12˚C to get to −12˚C.

  1. Look at this bank statement.

    Described image
    Figure 6 A bank statement
    • a.On which days was Sonia Cedar overdrawn, and by how much?

    • b.How much money was withdrawn between 9 and 11 of October?

    • c.How much was added to the account on 15 October?

Answer

  1.  

    • a.The minus sign (−) indicates that the customer is overdrawn, i.e. owes money to the bank.

      The amount shows how much they owe. So Sonia Cedar was overdrawn on 11 October by £20 and by £50 on 21 October.

    • b.£120 was withdrawn on 11 October.

      The customer had £100 in the account and must have withdrawn another £20 (i.e. £100 + £20 = £120 in total) in order to be £20 overdrawn.

    • c.The customer owed £20 and is now £70 in credit, so £90 must have been added to the account.

  1. Look at the table below showing a company’s profits over 6 months.

    Hint: a negative profit means that the company made a loss.

Table 6
MonthProfit (£000)
January166
February182
March−80
April124
May98
June−46
Balance 
  •  

    • a.Which month had the greatest profit?

    • b.Which month has the greatest loss?

    • c.What was the overall balance for the six months?

      Hint: start by calculating the total profits and the total losses.

Answer

  1.  

    • a.February had the largest profit with £182 000 (remember to look at the column heading which shows that the figures are in 000s – thousands).

    • b.March showed the greatest loss at £80 000.

    • c.To calculate the overall balance you need to first calculate the total profits and the total losses. To calculate the profits you need to do this calculation:

    • 166 + 182 + 124 + 98 = 570

    So the profit was £570 000.

    Next you need to calculate the total losses; two months showed a loss so you need to add these values:

    • 80 + 46 = 126 so the losses over the six months were £126 000.

    Now you can calculate the overall balance by subtracting the losses from the profits:

    • £570 000 − £126 000 = £444 000

    This is a positive value so it means the company made an overall profit of £444 000.

Summary

In this section you have:

  • learned the two main contexts in which negative numbers arise in everyday life – money (or debt!) and temperature

  • practised working with negative numbers in these contexts.


Did you know if you study a paid part-time course with the OU in Wales you could get up to £4,500* to help with your living costs?

Find out more

*Eligibility rules apply for financial support.