Answer:
£800
Step-by-step explanation:
For this question we need to utilise decimal multiplier. Since this is a decrease question to work out the decimal multiplier you have take 100 away from the percentage and then divide by 100. If this was an increase question then we would had to add 100 to the percentage and then divide by 100. Since the question is asking for the price before the decrease we are going to have to divide the multiplier by the price so,
⇒ Work out the multiplier by taking 100 away from the percentage and then dividing by 100
→ 100 - 20 = 80 ↔ 80 ÷ 100 = 0.8
⇒ The multiplier is 0.8, now we have to divide the multiplier by the price
→ 640 ÷ 0.8 = 800
The price of a washing machine was decreased by 20% to £640. The price before the decrease was £800
