Gethin is wallpapering a room in his house. He needs to add 3.5 litres of water to his wallpaper dry mix in order to make the correct consistency of paste. He has a measuring jug which measures up to 600ml when full.
How can he use the measuring jug to put exactly 3.5 litres of water in a bucket ready to mix?
This is a simple GCSE problem where students need to convert either millilitres to litres or vice versa. Students often get muddled between milli, kilo, centi or mega, and so this is a simple starter to consolidate units of measure. It takes most students less than a minute to solve, and as such, the extension questions often work well to stretch more able students.
Teachers could extend the learning by considering:
- This packet cost £2.85 and makes enough mix to hang 5 rolls of paper. How much has the wallpaper paste cost per roll (non-calc)?
- The packet contains 140ml of powder.
a) Express the powder to water as a simplified ratio
b) The mixed wallpaper paste is supposedly enough to hang 5 rolls. Gethin only needs to hang 2 rolls. How much paste will he have left after finishing the project (non-calc)?