Answer:
21
Step-by-step explanation:
Method 1:
[tex]p\%=\dfrac{p}{100}\\\\30\%=\dfrac{30}{100}=\dfrac{3}{10}=0.3\\\\30\%\ of\ 70\ is\\\\0.3\cdot70=21[/tex]
Method 2:
[tex]\begin{array}{cccc}100\%&-&70&\text{divide both sides by 10}\\\\10\%&-&7&\text{multiply both sides by 3}\\\\30\%&-&21\end{array}[/tex]
