Answer:
And if we solve for a we got
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the hourly rates of a population, and for this case we know the distribution for X is given by:
For this part we want to find a value a, such that we satisfy this condition:
(a)
(b)
Both conditions are equivalent on this case. We can use the z score again in order to find the value a.
As we can see on the figure attached the z value that satisfy the condition with 0.80 of the area on the left and 0.20 of the area on the right it's z=0.842. On this case P(Z<0.842)=0.8 and P(z>0.842)=0.20
If we use condition (b) from previous we have this:
But we know which value of z satisfy the previous equation so then we can do this:
And if we solve for a we got
This is fairly simple. Divide 2,871,000 by 10 and that's your answer!

Also, since you're dividing by a factor of 10 (or in this case, <em>10</em>) you can just take away as many places as are zeros in the number you're dividing from. This works for <em>10, 100, 1,000, 10,000, etc. </em>In this case, since there is only one zero in 10 you only take away one place marking, which gives you 287,100.
Answer:
Yes
Step-by-step explanation:
2•44=88
4•22=88
8•11=88
Answer:
x=1 y=4
Step-by-step explanation: