Answer:
First one is c because 3 1/2 - 1/2=3
Second one is also c because 0.9x2=1.8
And third one c is because 2 2/3:3/1=1 1/8
Standard deviation is: It is a measure of how spread out numbers are. It is the square root of the Variance, and the Variance is the average of the squared differences from the Mean.
For example: To find the standard deviation, you have to add up all the numbers in the data set, then divide by how many numbers there are, and that will get you your answer.
Example, Say your data set is: 9, 2, 5, 4, 12, 7, 8, 11, 9, 3, 7, 4, 12, 5, 4, 10, 9, 6, 9, 4.
The Mean is: 9 + 2 + 5 + 4 + 12 + 7 + 8 + 11 + 9 + 3 + 7 + 4 + 12 + 5 + 4 + 10+ 9 + 6 + 9 + 4. Over 20. That equals: 104 over 20 = 7.
So, the Standard Variance and Mean is: 7 for this problem.
Hope I helped!
- Debbie
<u>Number of terms = 48</u>
<u>common difference = 1.5</u>
This question involves the concept of Arithmetic Progression.
- The formula for sum of an arithmetic progression series with first and last term given is;
=
(a + l)
where;
a = first term
l = last term
n = number of terms
- From the given sequence, we see that;
first term; a = 4
last term; l = 76
Sum of A.P;
= 1920
- Plugging in relevant values into the sum of an AP formula, we have;
1920 =
(4 + 76)
simplifying this gives;
1920 = 40n
n = 1920/40
n = 48
- Formula for nth term of an AP is;
=
+ (n - 1)d
where;
is first term
d is common difference
n is number of term
is the nth term in question
the 48th term is 76
Thus;
76 = 4 + (48 - 1)d
76 - 4 = 47d
72 = 47d
d = 72/47
d ≈ 1.5
Thus;
Number of terms = 48
common difference = 1.5
Read more at; brainly.com/question/16935540
Y = 3x + 4 is the equation