15 is 30% of what number?
0.5 times 100 = 50... 50 is your answer
\(\displaystyle 15 = 30\% \cdot x \\ \\ x \cdot \frac{30}{100} =15 \\\\\\ x=15: \frac{30}{100} \\ \\ \\ x= ot15 \cdot \frac{100}{ ot30} \\ \\ \\ x= \frac{100}{2} \\ \\ \\ x=50\)
