Answer:
1. The rate, at which the students are entering the process is 4.5 students per minute.
2. On average a student spends 4 minutes on the cafeteria line.
Explanation:
10% of students does not enter the line.
therefore, percentage of students entering the line will be 100-10 = 90%.
The rate at which students enters the line will be 90% of overall students entering the cafeteria per minute:
[tex]\frac{90}{100}[/tex] × 5 ([tex]\frac{students}{minute}[/tex]
= 4.5 [tex]\frac{students}{minute}[/tex]
2. The average time spend by a student on the line will be:
the time rate of a student entering the line, which is the inverse of the rate of students entering the line : [tex]\frac{1}{4.5}[/tex] × the number of students waiting on the line, which is 18.
⇒ [tex]\frac{1}{4.5}[/tex] × 18 = 4 minutes.