Answer:
25
Explanation:
Since she predicts that 80% of the invited people come, she needs to invite a number greater than 20, so that 80% of that number is 20.
Let the number of invited people be x.
80% of x must be 20.
80% * x = 20
0.8x = 20
Divide both sides by 0.8
x = 25
Answer: She should invite 25 people.
Check: Let's find 20% of 25. If it is 20, then 25 is correct.
80% of 25 = 0.8 * 25 = 20
Since 80% of 25 is 20, the answer, 25, is correct.