Changing Ratios Changing Amounts

This resource teaches KS4 students taking the Higher paper how to approach questions where a ratio is given, a number added or subtracted and then a new ratio given.

The resource consists of a presentation, a worksheet and an activity. The activity is part of the presentation and worked solutions to the questions on the worksheet are also included.

The lesson starts by showing students how to approach questions where the initial amounts are given. An example of writing equivalent ratios involving the final ratio is given and understanding is tested with mini white board work.

This process is repeated for when the initial amounts are not known.

This process is again repeated for questions where the amount added to one initial amount is subtracted from the other.

Students are then shown how equivalent ratios are converted to equivalent fractions, to equations which are solved.

Understanding is consolidated using a matching activity.

There are some examples of solving complete problems before the students tackle the worksheet.