Answer:
51,200 people
Step-by-step explanation:
100% of the attendees = 64000. To find 80% of that number you multiply by the corresponding decimal to the percentage wanted. In this case, it is multiplied by .8.
Alternatively, you could set up a proportion.
100 * 80
64000 x
You cross multiply the 64000 and 80. Then you divide by 100.