Alright! To answer this question we first have to set up an equation to find percentages! The equation is as follows:
\(\frac{300}{1500}\) = \(\frac{x}{100}\) [Note: Percentages are out of 100]
Then we simply cross multiply (assuming you know how to):
We'd get 30000 = 1500(x).
Then we'd have to isolate the variable by dividing both sides by 1500:
\(\frac{30000}{1500}\) = \(\frac{1500x}{1500}\) → 20 = x
So, the crowd was reduced by 20% before the parachutists jumped!