Question

If there are 1500 guests, only 1 of them brought a coupon for free admission to the carnival?

Answer 1

So 1/50 brought the pass
x out 1500
1/50 = x/1500
cross multiply
1500 = 50x
divide both sides by 50
30 = x

You can expect for 30 out of the 1,500 to receive free admissions. 

Hope this helps