Answer:
He should prepare 320 cups of soup.
Explanation:
Given:
A chef planning for a large banquet think that 2 out of every 5 dinner guest will order his soup appetizer . He expects 800 guests at the banquet.
Now, to find the cups of soup he should prepare.
Let the number of cups he should prepare be

Total number of guests expected at the banquet hall = 800.
As, 2 out of every 5 dinner guest will order his soup appetizer.
So, 2 is equivalent to 5.
Thus,
is equivalent to 800.
Now, to get the number of cups by using cross multiplication method:

By cross multiplying we get:

Dividing both sides by 5 we get:

Therefore, he should prepare 320 cups of soup.