The prices of all college textbooks follow a bell-shaped distribution with a mean of $113 and a standard deviation of $12. Using the empirical rule, find the interval that contains the prices of 99.7% of college textbooks.

Step-by-step explanation:

In statistics, the empirical rule states that for a normally distributed random variable,

In mathematical notation, as shown in the figure below (for a standard normal distribution), the empirical rule is described as

where the symbol (the uppercase greek alphabet phi) is the cumulative density function of the normal distribution, is the mean and is the standard deviation of the normal distribution defined as .

According to the empirical rule stated above, the interval that contains the prices of 99.7% of college textbooks for a normal distribution ,

Therefore, the price of 99.7% of college textbooks falls inclusively between $77 and $149.

on your paper it doesn't say the answer but the the answer is altitude

step-by-step explanation:

fa tha first one you gonna add y to both sides

it look like this

x-y+y=6+y

x=y+6

therefore your answer is

x =y+6

fa tha second one

you gonna flip tha equation

it gonna look like x-4y=y

then add 4 to both sides

it gonna look like tha

x-4 +4 =y +4

so therefore tha answer is x=y+4

step-by-step explanation: