Find the scale.
a) Actual size $$12$$ $$m$$ Drawing size $$3$$ $$cm$$
b) Actual size $$45$$ feet Drawing size $$5$$ inches
As per question
a) By using scale,
= size drawn $$\div$$ actual size
$$ = 3 cm \div 12m$$
$$ = 1 cm \div 4m$$
Therefore, scale $$= 1cm : 4 m $$
b) By using scale,
= size drawn $$\div$$ actual size
$$ = 5$$ inches $$\div$$ $$45 feet$$
$$ = 1$$ inch $$\div$$ $$9 feet $$
Therefore, scale $$= 1$$ inch $$: 9$$ feet