Apolymer is manufactured in a batch chemical process. viscosity measurements show that it is approximately normally distributed with a standard deviation of 20. a random sample of 42 batches has a mean viscosity of 759. construct a 99% confidence interval around the true population mean viscosity.

(751.05, 766.95)

Step-by-step explanation:

We know that the confidence interval for population mean is given by :-

,

where =population standard deviation.

= sample mean

n= sample size

z* = Two-tailed critical z-value.

Given :  

n= 42

We know that from z-table , the two-tailed critical value for 99% confidence interval : z* =2.576

Now, the 99% confidence interval around the true population mean viscosity :-

∴ A 99% confidence interval around the true population mean viscosity : (751.05, 766.95)

step-by-step explanation:

a child is 12 years old, and his father is 32 years older. in how many years will the age of the father be 2 times the age of the child?

******************

this needs to be the answer format, or else your answer is incomplete.

if the number of years is x, then the equation is

in __ years

answer: your answer is a