Answer:

Step-by-step explanation:
If we assume that the number of arrivals is normally distributed and we don't know the population standard deviation, we can calculated a 95% confidence interval to estimate the mean value as:

where x' is the population mean value, x is the sample mean value, s is the sample standard deviation, n is the size of the sample,
is equal to 0.05 (it is calculated as: 1 - 0.95) and
is the t value with n-1 degrees of freedom that let a probability of
on the right tail.
So, replacing the mean of the sample by 49, the standard deviation of the sample by 17.38, n by 10 and
by 2.2621 we get:

Finally, the interval values that she get is:

You can use a online calculator it really helps
Solution
Step 1
Expand the brackets
8(9r-1) - 9(-8r + 2)
72r - 8 +72r -18
Step 2
Bring like terms together
72r + 72r -8 -18
Step 3
Sum and get the expression in its simplest for after factorization
144r -26
After factorization we will have in its simplest form the following answer
2 (72r -13)
Answer:
460
Step-by-step explanation: multiply all numbers to get your answer
To increase an amount by 19% you need to multiple the amount by 1.19