2. The amount of Electricity used is measured in units To calculate the amount used we use the following formula Units used = PRESENT reading - PREVIOUS reading Meter Reading PresentPrevious 3251432347 Meter Reading PresentPrevious 6013459929 Units used = 32514 - 32347 = 167 Units used = 60134 - 59929 = 205

3. Calculate the units used for each of the following sets of readings PresentPrevious 4106740878 2310722939 8107480873 0045300269 Units = 41067 - 40878=189 Units = 23107 - 22939= Units = 81074 - 80873 = Units = 00453 - 00269 = 168 201 184 We can calculate the cost of the electricity using Total cost = units used x cost per unit Find the cost of 125 units of electricity at 6p per unit Cost =125 x 6 =750p =£7.50

4. Electricity Bills Calculate the total cost for each of the following 1.34123349 2.60355950 3.10230881 4.08940782 5.04020324 PresentPrevious 1 unit of electricity costs 4p Units usedTotal cost 63 85 142 112 78 252p = £2.52 340p = £3.40 568p = £5.68 448p = £4.48 312p = £3.12

5. Other costs on an electricity bill Standing charge - this is a fixed amont of money paid even if no electricity is used VAT is paid on the total electricity bill

6. Bright Spark Electricity House H. Old, 3 This Street 11/09/96 - 14/12/96 Meter ReadingChargesAmount PresentPrevious 20651876 units at 8p Standing charge Sub-total VAT at 17.5% Total Due £12.50 189 £15.12 £27.62 £4.83 £32.45