A(n)=-1(-3^n)
3, -9, 27, -81
Subtract
from both sides to get



Answer:
99.7% of customers have to wait between 8 minutes to 30 minutes for their food.
Step-by-step explanation:
We are given the following in the question:
Mean, μ = 18 minutes
Standard Deviation, σ = 4 minutes
We are given that the distribution of amount of time is a bell shaped distribution that is a normal distribution.
Empirical Formula:
- Almost all the data lies within three standard deviation from the mean for a normally distributed data.
- About 68% of data lies within one standard deviation from the mean.
- About 95% of data lies within two standard deviations of the mean.
- About 99.7% of data lies within three standard deviation of the mean.
Thus, 99.7% of the customers have to wait:

Thus, 99.7% of customers have to wait between 8 minutes to 30 minutes for their food.
The answer is: "72" .
______________________________________________
(input value, or "x") / 10 = y = f(x);
When y = 7.2, what is the value of "x" ?
x / 10 = 7.2 ;
x = (7.2) * 10 = 72 .
_______________________
Answer:
4.8
Step-by-step explanation:
Multiply 5*4.8 equal 21.6