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
The perimeter of these can be found by adding length and width and then multiplying by two.
Rectangle A: (with all of the variables already doubled)
2x + 16 + 2x - 2
2x + 2x + 16 - 2
4x + 14
So rectangle A's perimeter is 4x + 14.
Rectangle B: (Still with all the variables already doubled)
8x + 10 + 6x - 4
8x + 6x + 10 - 4
14x + 6
So rectangle B's perimeter is 14x + 6
And now to subtract the two.
(7x + 3) - (4x + 14)
14x + 6 - 4x - 14
14x - 4x + 6 - 14
10x - 8
So it would be C.
Answer:
40.49cm²
Step-by-step explanation:
I hope it helps
3 1/2 cm or 3.5 cm. Because you should divide 280 by 80 which equals 3.5. turn 3.5 to centimeters. Thats your answer.
In the hundreds place so its 300