Respuesta :
in plain and short, we simply divide the whole £300 by (3+7), and distribute accordingly.
[tex]\bf 300\qquad 3:7\qquad \cfrac{3}{7}~\hspace{5em}\cfrac{3\cdot \frac{300}{3+7}}{7\cdot \frac{300}{3+7}}\implies \cfrac{3\cdot 30}{7\cdot 30}\implies \cfrac{90}{210}\implies 90:210[/tex]
1. add the ratio together: 3+7=10
2. do £300 divided by 10 = £30
3. do £30 X 3 which equals £90
4. do £30 X 7 which equals £210
The ratio is £90:£210
