Suppose you, along with 7 of your friends ate a medium pizza cut into 8 equal parts. Since all of you remained hungry after that, you ordered one more pizza. This time a large pizza, which is again cut into 8 equal parts. The percentage of the full large pizza eaten by you will be
the same as that of the medium pizza.
We can see this example as a pie chart. In the medium pizza, small pie chart, the chart is divided into 8 equal parts. So, the percentage of pizza eaten by you is 18x100. Similarly, in large pizza, similar pie chart which is again divided into 8 equal parts, the percentage of pizza eaten by you is again 18x100. So, the percentage of large pizza eaten by you will be same as the percentage of medium pizza eaten by you.