Answer:


And tha's equivalent to use this formula:


Step-by-step explanation:
For this case the 95%of the values are between the following two values:
(75 , 163)
And for this case we know that the variable of interest X "length of a movie" follows a normal distribution:

We can estimate the true mean with the following formula:

Now we know that in the normal standard distribution we know that we have 95% of the values between 1.96 deviations from the mean. We can find the value of the deviation with this formula:


And tha's equivalent to use this formula:


Answer:
The width is 3cm
Step-by-step explanation:
Since the area of the rectangle is 27cm² and the length is 9cm you can just divide 27 by 9 to find out the width of the rectangle
Answer:
Step-by-step explanation:

Answer:
-10
Step-by-step explanation: