Answer:
The number of minutes advertisement should use is found.
x ≅ 12 mins
Step-by-step explanation:
(MISSING PART OF THE QUESTION: AVERAGE WAITING TIME = 2.5 MINUTES)
<h3 /><h3>Step 1</h3>
For such problems, we can use probability density function, in which probability is found out by taking integral of a function across an interval.
Probability Density Function is given by:

Consider the second function:

Where Average waiting time = μ = 2.5
The function f(t) becomes

<h3>Step 2</h3>
The manager wants to give free hamburgers to only 1% of her costumers, which means that probability of a costumer getting a free hamburger is 0.01
The probability that a costumer has to wait for more than x minutes is:

which is equal to 0.01
<h3>
Step 3</h3>
Solve the equation for x

Take natural log on both sides

<h3>Results</h3>
The costumer has to wait x = 11.53 mins ≅ 12 mins to get a free hamburger
You need to measure the angles wich means that u use a protractor if the angle is 90 degrees is a straight angle if it is below 90 degrees is acute and if it is above 90 degrees it's obtuse
I-1 is the polynomials because I is the linear term and 1 is the constant
Let the # be n.
Then 8(1/n) = 4(1/6). Mult both sides by 6n to elim. the fractions:
6n(8) 6n(4)
------- = -------- => 48 = 4n, and so n = 12 (answer)
n 6