Here is another one that I am having trouble with.

Question

Julio works as a quality control expert in a beverage factory.The assembly line that he monitors produces about 20,000 bottles in a 24-hour period. Julio samples about 120 bottles an hour and rejects the line if he finds more than 1/50 of the sample to be defective. About how many defective bottles should Julio allow before rejecting the entire line?

Again, I do not want the ANSWER, I need to understand the equation to use to solve it.

Answer 1

1/50 * 120 = ?

or
0.02 * 120 = ?

Answer 2

2.40 i think

Answer 3

Right. So when Julio finds the third defective bottle in his sample, he needs to reject the entire line.