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:


It's how far a number is from 0.
( ex.) 6 is 6 away from 0 but so is -6; so the absolute value of 6 is 6 and the absolute value of -6 is 6. the symbol "|" is placed on either side to mean absolute value.
(ex.2) |-6| = 6. -|-6|= -6. |6|=6. and -|6|= -6.
if the negative sign is outside of the symbol then the number will always be negative but if there is no negative sign outside of the symbol it will always be positive, even if it looks lile this. |-6| it would still be positive.
The tablecloth would have to be 4 feet wide to use all of the fabric. 30=7.5x is the equation to solve this problem. You need to use reverse operations, so 30/7.5=4.
The answer i got was
-89/x-9x-10