Answer:
6
Step-by-step explanation:
Variance = summation of (x - mean)^2 all divided by the number of dataset.
mean = (17 + 5 + 11 + 1 + 11)/5 = 9
Variance = [(17 - 9)^2 + (5 - 9)^2 + (11 - 9)^2 + (1 - 9)^2 + (11 - 9)^2]/5 = (8^2 + (-4)^2 + 2^2 + (-8)^2 + 2^2}/5 = (64 + 16 + 4 + 64 + 4)/5 = 152/5 = 30.4
If the original angle is x degrees then its supplement is 180 - x degrees.
we have the equation:-
180 - x = 3x + 20
160 = 4x
x = 40
The original angle is 40 degrees and its supplement is 140 degrees
To divide by a fraction, multiply by the reciprocal of that fraction.
1/3 • 5/1 or 1/3 • 5
Calculate the product straight across.
1/3 • 5/1 = 5/3
<h3>Key points :-</h3>
᪥ The formula to find the 31st term is : 
᪥ In the formula, 
represents the first term of the sequence.
᪥ 
is the number of terms, In our case n is 31.
᪥ 
is the common difference between the terms, In our case d is 4.
<em>Detailed Solution is attached</em>᭄
