Answer:
x= -3
Step-by-step explanation:
Answer:
For a height of 66 inches, Z = 0.65.
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the z-score of a measure X is given by:
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
The average height was about 64.3 inches; the SD was about 2.6 inches.
This means that ![\mu = 64.3, \sigma = 2.6](https://tex.z-dn.net/?f=%5Cmu%20%3D%2064.3%2C%20%5Csigma%20%3D%202.6)
66 inches:
The z-score for a height of 66 inches is:
![Z = \frac{X - \mu}{\sigma}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7BX%20-%20%5Cmu%7D%7B%5Csigma%7D)
![Z = \frac{66 - 64.3}{2.6}](https://tex.z-dn.net/?f=Z%20%3D%20%5Cfrac%7B66%20-%2064.3%7D%7B2.6%7D)
![Z = 0.65](https://tex.z-dn.net/?f=Z%20%3D%200.65)
For a height of 66 inches, Z = 0.65.
Add up the digits: 1+7+4 = 8+4 = 12
We can see that 12 is a multiple of 3, so that means 174 is also a multiple of 3
Note: 12's digits add to 1+2 = 3 further confirming that 12 is a multiple of 3
So 174 is divisible by 3. We can divide 174 over 3 and get a whole number result
174/3 = 58 with no decimal portion or remainder.
30% = 3/10
Number of hours you sleep = 24hours × 3/10
= 24hours ÷ 10 × 3
= 2.4hours × 3
= 7.2hours
Hope this helps! :)