B and C are correct because you do basic PEMDAS and get 58 for both those expressions. If this is right could you possibly give me brainliest? Hope this helped.
Answer:
16 rounded to the nearest 10 is 20
21 rounded to the nearest 10 is 20
so I don't really know but I guess you should put the x as 20 for sure UwU
Answer:
That looks confusing
Step-by-step explanation:
Answer:
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.
Step-by-step explanation:
We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:
Now, we have to find z in the Ztable as such z has a pvalue of .
So it is z with a pvalue of , so
Now, find M as such
In which is the standard deviation of the population and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 0.181 - 0.0140 = 0.167 cc/m³.
The upper end of the interval is the sample mean added to M. So it is 0.181 + 0.0140 = 0.195 cc/m³.
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.