Answer:
13
Step-by-step explanation:
where n is the number of terms, a1 is the first term and an is the last term. The sum of the first n terms of an arithmetic sequence is called an arithmetic series . Example 1: Find the sum of the first 20 terms of the arithmetic series if a1=5 and a20=62 .An arithmetic sequence is a sequence where the difference between any two consecutive terms is a constant. ... As with any recursive formula, the initial term of the sequence must be given. An explicit formula for an arithmetic sequence with common difference d is given by an=a1+d(n−1) a n = a 1 + d ( n − 1 ) .
Answer:
$19.55
Step-by-step explanation:
17*0.15=2.55
17+2.55=19.55
Answer:
8.2+/-0.25
= ( 7.95, 8.45) years
the 95% confidence interval (a,b) = (7.95, 8.45) years
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x+/-zr/√n
Given that;
Mean x = 8.2 years
Standard deviation r = 1.1 years
Number of samples n = 75
Confidence interval = 95%
z value(at 95% confidence) = 1.96
Substituting the values we have;
8.2+/-1.96(1.1/√75)
8.2+/-1.96(0.127017059221)
8.2+/-0.248953436074
8.2+/-0.25
= ( 7.95, 8.45)
Therefore the 95% confidence interval (a,b) = (7.95, 8.45) years
<u>Answer:</u>
, 
, 
, 
<u>Step-by-step explanation:</u>
First, we subtract 128 from both sides:
Then, we subtract 
from both sides:
Rewrite the equation:
Insert and solve:
<em>Please give Brainliest</em>
Two or more angles whose sum is 180° are called supplementary angles. The measure of the ∠y is 120°.
<h3>What are supplementary angles?</h3>
Two or more angles whose sum is 180° are called supplementary angles. If a straight line is intersected by a line, then there are two angles form on each of the sides of the considered straight line. Those two-two angles are two pairs of supplementary angles. That means, that if supplementary angles are aligned adjacent to each other, their exterior sides will make a straight line.
Given the puck strikes the wall at an angle of 30°, it goes away at the same angle of 30°. Therefore, the measure of angle y can be found using the sum of the angle as a supplementary angle. Thus, we can write,
30° + ∠y + 30° = 180°
60° + ∠y = 180°
∠y = 180° - 60° = 120°
Hence, the measure of the ∠y is 120°.
Learn more about Supplementary Angles:
brainly.com/question/2882938
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