An index for public sector pay was 100 in Jan 2010. By May 2012, it had risen to 104.5.
By what percentage, approximately, did public sector pay increase between Jan 2010 and May 2012?
choose your answer.

Answer options:

104

105

How to approach this question

The base year index is 100. The new index is 104.5. The percentage increase is simply the new index value minus the base index value (100). Calculate this difference and then round to the nearest whole number.

Full Answer

B.5✓ Correct

Index numbers are used to show percentage changes over time relative to a base period. The base period is always given an index value of 100. The index for Jan 2010 (the base period) is 100. The index for May 2012 is 104.5. The percentage change from the base period is calculated as: Percentage change = New Index Value - Base Index Value Percentage change = 104.5 - 100 = 4.5%. The question asks for the approximate percentage increase, so we round 4.5% to the nearest whole number, which is 5%.

Common mistakes

✗ Choosing 104 or 105, which are the index values, not the percentage change. ✗ Rounding 4.5 down to 4 instead of up to 5.

Question 17.1 All questions Question 17.3

Practice the full AQA GCSE Statistics Foundation Tier Paper 1

47 questions · hints · full answers · grading

More questions from this exam

Q01An ordinary fair dice is rolled. Circle the probability of rolling a 4.Easy Q02What is the statistical name given to the removal or correction of apparently incorrect values fr...Easy Q03Circle the word that completes this sentence correctly. This diagram shows data with a negative _...Easy Q04Which of these sample sizes from a large population gives the most reliable sample? Choose your a...Easy Q05.1Antonio makes and sells flower displays. He keeps a record of each display he makes. Below is one...Easy

View all 47 questions →