## Percentage increase of service costs

 Difficulty: Rating: GCSE Marks:

GCSE Text:
In 2010, George’s garage charged £160 for a minor service, and £330 for a major service. In 2015, George’s prices had increased to £180 for a minor service, and £355 for a major service.

a) Calculate the percentage increase in the price of a minor service over those 5 years.

b) Calculate the percentage increase in the price of a major service over those 5 years.

c) Which service type has increased by the highest percentage?

Suggestions:
A typical ‘what is one value as a percentage of another?’ type GCSE question that could appear on either Higher or Foundation papers. Students commonly struggle to know which price to use as the denominator of the fraction – the increased price or the original price? They also have to take care to use the difference as the numerator too, so quite often many answers are proposed by students. It is then useful to ask them to check it by finding that percentage of the original and then making sure that you get back to the price in the question.

Extension Ideas:
Teachers could extend the learning by considering:

• George hasn’t put his service prices up since 2015, and feels that he must implement an 8% increase in both prices over the next 2 years. What will be the new prices in 2 years if he does that?