The sum of the first 20 terms of an arithmetic sequence with the 18th term of 8.1 and a common difference of 0.25 is 124.5
Given,
18th term of an arithmetic sequence = 8.1
Common difference = d = 0.25.
<h3>What is an arithmetic sequence?</h3>
The sequence in which the difference between the consecutive term is constant.
The nth term is denoted by:
a_n = a + ( n - 1 ) d
The sum of an arithmetic sequence:
S_n = n/2 [ 2a + ( n - 1 ) d ]
Find the 18th term of the sequence.
18th term = 8.1
d = 0.25
8.1 = a + ( 18 - 1 ) 0.25
8.1 = a + 17 x 0.25
8.1 = a + 4.25
a = 8.1 - 4.25
a = 3.85
Find the sum of 20 terms.
S_20 = 20 / 2 [ 2 x 3.85 + ( 20 - 1 ) 0.25 ]
= 10 [ 7.7 + 19 x 0.25 ]
= 10 [ 7.7 + 4.75 ]
= 10 x 12.45
= 124.5
Thus the sum of the first 20 terms of an arithmetic sequence with the 18th term of 8.1 and a common difference of 0.25 is 124.5
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<span>3√20/√5
= </span>3 √4 √5<span> / √5
= 3 * 2
= 6
answer is </span><span>b)6</span>
Answer:
Step-by-step explanation:
You want to leave a 15% tip on a meal that cost $48.
First, convert the 15% to an actual number that can be used in a calculation. For percents,this is always done by simply dividing the percent (in this case 15%) by 100%.So, the conversational term "15%" becomes 15% / 100% = 0.15 in terms of a real mathematical number.
Second, you need to find out what 15% of your $48 meal cost is.This is always done by multiplying 0.15 by $48.00, or
0.15 x $48.00=$7.20.
So, the amount of tip you are going to leave is $7.20.
This makes the total cost of your meal (to write on your charge slip or other payment)
$48.00 + $7.20 = $55.20.
i hope this may come to use to your rude a s s
Answer:
Step-by-step explanation:
A perpendicular bisector is a special kind of segment, ray, or line that. (1) intersects a given segment at a 90° angle, and. (2) passes through the given segment's midpoint. Segment CD is the perpendicular bisector to segment AB. We derive two important theorems from the characteristics of perpendicular bisectors.
Answer:
Give me brainliest first and i will give u the answer
Step-by-step explanation:
