The Empirical Rule applies to a normal, bell-shaped curve and states that within one standard deviation of the mean (both left-side and right-side) there is about 68% of the data; within two standard deviations of the mean (both left-side and right-side) there is about 95% of the data; and within three standard deviations of the mean (both left-side and right-side) there is about 99.7% of the data. See display below from Section 3.3 Measures of Variation in the textbook.
Example: IQ Scores have a bell-shaped distribution with a mean of 100 and a standard deviation of 15. What percentage of IQ scores are between 70 and 130?
<span>Solution: </span>130 – 100 = 30 which is 2(15). Thus, 130 is 2 standard deviations to the right of the mean. 100 – 70 = 30 which is 2(15). Thus, 70 is 2 standard deviations to the left of the mean. Since 70 to 130 is within 2 standard deviations of the mean, we know that about 95% of the IQ scores would be between 70 and 130.
Answer:
8
Step-by-step explanation:
Answer: y = -1
Step-by-step:
-8y + 1 = -9y
Subtract 1 from both sides
-8y = -9y-1
Add 9y to both sides to isolate y
y = -1
Answer:
That would be negative 45 or - 45
Please correct me if im wrong
Step-by-step explanation:
hii I wanna ask something