Step-by-step explanation:
In statistics, the empirical rule states that for a normally distributed random variable,
- 68.27% of the data lies within one standard deviation of the mean.
- 95.45% of the data lies within two standard deviations of the mean.
- 99.73% of the data lies within three standard deviations of the mean.
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.
Answer:
its 2
Step-by-step explanation:
Answer: 9.3 ×
Step-by-step explanation: To write a number in scientific notation, first write a decimal point in the number so that there is only one digit to the left of the decimal point.
In this case, we can write 93,000,000 as 9.3000000 and notice that there is only one digit to the left of the decimal point.
Next, we count the number of places the decimal point would need to move to get back to the original number which is 93,000,000.
Since we will need to move the decimal point seven places to the left, we have an exponent of positive 7. Our exponent will be positive because we need to move the decimal point seven places to the right. Now, we can write our number in scientific notation.
9.3 ×
<span>A quantity representing the power to which a fixed number (the base) must be raised to produce a given number..</span>