Ratios are used in everyday life and can help you work out problems including scale drawings and reading maps.
In a scale drawing, all dimensions have been reduced by the same proportion.
A model boat is made to a scale of . This scale can be applied to any units, so measured on the model is on the actual boat, measured on the model is on the actual boat.
a) If the model boat is wide, how wide is the actual boat?
b) If the boat has a mast of height , how high is the mast on the model?
The scale is . This means that every on the model is equivalent to on the boat.
The mathematical symbol for equivalent is: ≡
a) on the model ≡ on the boat
on the model ≡ (or ) on the boat
b) on the boat ≡ on the model
So, because: ,
(or ) on the boat ≡ on the model