From AQA comes an outstanding resource, GCSE Mathematics: 90 maths problem  solving questions.

Em  @EJmaths has a brilliant PowerPoint with all the questions and answers – see it here.
Note the very clear indices at the end of the document, by Content area and also by Strategy.

AQA GCSE Problem Solving Questions

AQA GCSE Problem Solving Questions

Don Steward – Ratio Problems

From Don Steward many fantastic problems on Ratio also a small number tagged Ratio Sharing

Nrich of course, a search on Ratio returns this selection of problems. Nrich problems always include teacher’s notes and solutions.

The new GCSE specification includes: “relate ratios to fractions and to linear functions”. Use the excellent Desmos graphing calculator to demonstrate examples; taking an exemplification question from AQA I created a Desmos page to illustrate the problem.

Just as one can always find something on Nrich, the same is true of CIMT. From the Centre for Innovation in Mathematics Teaching we have Ratio and Proportion from the Year 8 book (UK age 12-13) and Variation from the GCSE course (UK age 14-16). As well as the Year 8 text, further resources are available such as Activities.  Other teacher resources include slides and Revision Tests (you will need the CIMT password for some resources).

These sorts of problems must be on everybody’s Mathematics specifications all over the world! In the UK there is an increased emphasis on Ratio and Proportion in the new GCSE specifications; a link to these resources has been included on the GCSE New Content page.