Answer:

Step-by-step explanation:
In order to write the series using the summation notation, first we need to find the nth term of the sequence formed. The sequence generated by the series is an arithmetic sequence as shown;
4, 8, 12, 16, 20...80
The nth term of an arithmetic sequence is expressed as Tn = a +(n-1)d
a is the first term = 4
d is the common difference = 21-8 = 8-4 = 4
n is the number of terms
On substituting, Tn = 4+(n-1)4
Tn = 4+4n-4
Tn = 4n
The nth term of the series is 4n.
Since the last term is 80, L = 4n
80 = 4n
n = 80/4
n = 20
This shows that the total number of terms in the sequence is 20
According to the series given 4 + 8 + 12 + 16 + 20+ . . . + 80
, we are to take the sum of the first 20terms of the sequence. Using summation notation;
4 + 8 + 12 + 16 + 20+ . . . + 80 = 
It would be 2/10, or 1/5, since two out of the 10 numbers are even. 2/10 simplifies to 1/5, since there is 1 for every 5 numbers.
We could turn this into a percentage by dividing 1 by 5, which gives us 0.2. Then we can multiply by 100 to get 20.
So, our probability of choosing an even number is:
2/10
OR
1/5
OR
20%
Hope I could help!
Answer: A.

Step-by-step explanation:
Null hypothesis
: A statement describing population parameters as per the objective of the study. It usually takes "≤,≥,=" signs.
Alternative hypothesis
: A statement describing population parameters as per the objective of the study. It usually takes ">, <, ≠" signs.
Let p be the proportion of screens that will be rejected.
12 percent of the screens manufactured using a previous process were rejected at the final inspection.
(i.e. p= 0.12)
Objective of the study = whether the new process<em> reduces </em>the population proportion of screens that will be rejected
i.e. p< 0.12
So, the appropriate hypotheses to investigate whether the new process reduces the population proportion of screens that will be rejected:

There's my answer
25/100
27/108
31/124
these three equal 1/4 or 1:4
I hope that right
Folded mountain with waves, twists, and turns. I believe because the article stated it was gradual and various patterns were formed.