Try some yourself

Activity 62

Give examples of all the rules for the division of and by positive and negative numbers.

Answer

Your list should look something like this.

   Dividing a positive number by a positive number gives a positive answer.

   4 ÷ 2 = 2.

   Dividing a negative number by a positive number gives a negative answer.

   4 ÷ 2 = 2.

   Dividing a positive number by a negative number gives a negative answer.

   4 ÷ 2 = 2.

   Dividing a negative number by a negative number gives a positive answer.

   4 ÷ 2 = 2.

Activity 63

Evaluate each of the following and where possible give an example from everyday life to illustrate the calculation.

  • (a) 24 ÷ 4

  • (b) 40 ÷ 4

  • (c) 45 ÷ 15

Answer

  • (a) 24 ÷ 4 = 6

  • Thomas has lots of £4 IOUs. A gift of £24 will subtract 6 of them.

  • (b) 40 ÷ 4 = 10

  • An IOU of £40 divided into smaller IOUs of £4 each (which could be paid off more easily from Thomas’s pocket money) gives 10 smaller IOUs.

  • (c) 45 ÷ 15 = 3

  • A debt of £45 shared between 15 people means each owes £3.

Activity 64

Evaluate each of the following.

  • (a) 7 × 6

  • (b) 56 ÷ 7

Think of a financial context where each might be an appropriate calculation (bear in mind that negative numbers can represent debts).

Answer

  • (a) 7 × 6 = 42

  • (7 debts of £6 result in a debt of £42).

  • (b) 56 ÷ 7 = 8

  • (a £56 debt divided into £7 debts gives eight £7 debts).

If you have a calculator check that it gives the same answers as yours.