Answer:
{13.7756,18.2244}
Step-by-step explanation:
Given the sample size, the margin of error can be calculated with the formula 
where Z is the critical value for the desired confidence level, σ is the population standard deviation, and n is the sample size. Therefore, our margin of error for a 90% confidence level is:
The formula for a confidence interval is 
where x-bar is the sample mean. Therefore, the 90% confidence interval for the mean amount of sushi pieces a person can eat is:
![CI=\bar{x}\pm[M]=16\pm2.2244={13.7756,18.2244}](https://tex.z-dn.net/?f=CI%3D%5Cbar%7Bx%7D%5Cpm%5BM%5D%3D16%5Cpm2.2244%3D%7B13.7756%2C18.2244%7D)
Therefore, we are 90% confident that the true mean amount of sushi pieces a person can eat is contained within the interval {13.7756,18.2244}
There are 50 seats on the tour bus. You reserve 2/5 of the seats How many seats did you reserve
Area shaded = Area big circle- Area of small circle;
200 pi= pi•(2x)^2 -pi•6^2;
200pi= pi•4x^2 -pi•36;
200pi=pi•4(x^2 -9) divide both sides by 4pi;
50=x^2 -9; So x=sqrt(59)~7.68cm
Discriminant = square root (b^2 -4*a*c)
square root (64 -4*1*12) =
square root (16) =
4
Therefore it has 2 rational soltions
45 hours.
80 - 70= 10, and 450/10 is 45.
to justify, you can do 70x45= 3,150, and 80x45= (3,600 - 3,150= 450)
