Answer:
2.2*10^5
Step-by-step explanation:
to write a # in scientific notation change the # to decimal form.
so 2.2
then move the decimal point to the right until you get the original #
Answer:
The 95 percent confidence interval for the true mean metal thickness is between 0.2903 mm and 0.2907 mm
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 the margin of error 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 0.2905 - 0.0002 = 0.2903 mm
The upper end of the interval is the sample mean added to M. So it is 0.2905 + 0.0002 = 0.2907 mm
The 95 percent confidence interval for the true mean metal thickness is between 0.2903 mm and 0.2907 mm
Answer:
There will be 104 customers a day, after advertising campaign
Step-by-step explanation:
Current number of customers in a day in shop = 80
After advertising campaign, the customers will increase = 30%
So, new customers will be:
We can find new customers by adding new 30% customers to the current 80 customers.
First find 30% of 80

Now, add 24 to current 80 customers.
Number of customers = 80+24 = 104
So, there will be 104 customers a day, after advertising campaign
BBB it is b the answer is b