Answer:
The number is -1/2
Step-by-step explanation:
Let x be the number
2x+8 = 7
Subtract 8 from each side
2x+8-8 = 7-8
2x = -1
Divide each side by 2
2x/2 =-1/2
x = -1/2
The number is -1/2
Answer:
Part (a) The value of Z is 0.10396. Part (b) The value of Z is 0.410008.
Step-by-step explanation:
Consider the provided information.
Part (a)
In order to find the number z such that the proportion of observations that are less than z in a standard Normal distribution is 0.5414, simply find 0.5414 in the table and search for the appropriate Z-value.
Now, observing the table it can be concluded that the value of Z is 0.10396.
Part (b)
Consider the number 65.91%
The above number can be written as 0.6591.
Now, find 0.6591 in the table and search for the appropriate Z-value.
By, observing the table it can be concluded that the value of Z is 0.410008.
See photo. I hope it helps
Answer:
c. 3.6 and 10.4 hrs
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviations of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean 7, standard deviation 1.7.
For about 95% of students, nightly amount of sleep is between
7 - 2*1.7 = 7 - 3.4 = 3.6 hours
7 + 2*1.7 = 7 + 3.4 = 10.4 hours
So the correct answer is:
c. 3.6 and 10.4 hrs
