Answer:
Step-by-step explanation:
<u>Concept: </u>
Here, we need to know the idea of a special triangle 30-60-90.
A special right triangle is a right triangle with some regular feature that makes calculations on the triangle easier, or for which simple formulas exist.
The ratio between the corresponding side of each angle is 1 : √3 : 2
If you are still confused, please refer to the attachment below for a graphical explanation.
<u>Solve:</u>
30-60-90 ⇔ 1 : √3 : 2
Given the side corresponding to 90° is 20
30° : 90° = 1 : 2
30° : 20 = 1 : 2
30° = 10
30° : 60° = 1 : √3
10 : 60° = 1 : √3
60° = 10√3
Hope this helps!! :)
Please let me know if you have any questions
Answer:
a. 12
b. 7.200 and 2.683
Step-by-step explanation:
The computation is shown below:
Given that
P = 0.40 and n = 30
a)
The expected value of received e-mails is
= n × p
= 30 × 0.4
= 12
b)
The variance of emails received is
= n × p × (1 - p)
= 30 × 0.4 × 0.6
= 7.200
Now
The standard deviation of emails received is
= sqrt(variance)
= 2.683
We simply applied the above formula
