# GMC3: Working with proportion

This list contains a collection of resources to help meet General Mathematical Competency 1 (GMC1). More resources to support T level Science can be found on our T Level science resource packages page.

GMC3 states:

Students should:

• Be able to test for situations where two variables are directly proportional
• Be able calculate magnification from the size of the image and the size of the object
• Understand that an empirical formula represents the simplest ratio of atoms of each element in a compound and to be able to calculate an empirical formula
• Understand how to use the empirical formula and relative molecular mass to work out the molecular formula of a compound
• Understand the link between balanced equations and the ratio of moles of a substance in a reaction.
• Recognise other types of proportionality: inverse, square, inverse square
• Appreciate the different representations of different kinds of proportionality: numerical, algebraic and graphical representation
• Understand the links between fractions, percentages, ratios and proportion