1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Rudiy27
3 years ago
5

Write the series using summation notation. 4 + 8 + 12 + 16 + 20+ . . . + 80

Mathematics
1 answer:
zhannawk [14.2K]3 years ago
4 0

Answer:

\sum ^{20} _{n \to \11} 4n

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  = \sum ^{20} _{n \to \11} 4n

You might be interested in
Solve for x in triangle
fenix001 [56]
X=60degrees

bc you find 180-125 bc it is a straight angle. You get 55 degrees. Then you add 65+55=120. 180-120=60 degrees. This is because every triangle must have a sum of angles that equals 180 degrees.

Hope this helps.
7 0
2 years ago
Pls help and answer quick!! <br><br> find x
siniylev [52]

hi

I Don't know

sorry

I will try to say next time

6 0
2 years ago
.
Sholpan [36]

Answer:

Larry must mow approximately 25 lawns before he starts making a profit

Step-by-step explanation:

8 0
3 years ago
Given that f(x) = x^2 - 4x +1, find the value of m if f(m) = -3
iragen [17]

a. Answer:  m = 2

<u>Step-by-step explanation:</u>

f(x) = x² - 4x + 1

f(m) = m² - 4m + 1 = -3

         m² - 4m + 4 = 0

         (m - 2)(m - 2) = 0

               m = 2

***************************************************

b. Answer:  k = 2 and k = 5

<u>Step-by-step explanation:</u>

f(x) = x² - 7x + 14

f(k) = k² - 7k + 14 = 4

        k² - 7k + 10 = 0

        (k - 2)(k - 5) = 0

        k = 2   k = 5

3 0
3 years ago
The length of a rectangle is three times it’s width. The perimeter of the rectangle is 100 inches. What are the dimensions of th
BabaBlast [244]

Answer:

let the width be x inches

then the length would be 3x inches

perimeter of rectangle = p = 2(l+b)

100= 2(3x+x)

100= 2(4x)

100=8x

x=100/8

x=12.5 inches

thw width is 12.5 inches and length is 3*12.5=37.5 inches

Step-by-step explanation:

8 0
3 years ago
Other questions:
  • Points A, B, C, and D lie on a line consecutively so that AB = BC = CD = 6 in. Find the distance between the midpoints of segmen
    7·1 answer
  • Consider the following function f(x)=2x/3x^2-3 what is the domain of the function and what is the range of the function
    13·2 answers
  • I worked out this problem (but what I came up with was what that google photo says. I checked multiple times but no luck. Can I
    12·1 answer
  • <img src="https://tex.z-dn.net/?f=f%3D%20%20%5Cfrac%7B9%7D%7B5%7Dc%20%2B%2032" id="TexFormula1" title="f= \frac{9}{5}c + 32" al
    14·1 answer
  • Geometry question please help
    13·1 answer
  • The question is on the image
    8·1 answer
  • Answer this please.!
    6·1 answer
  • Pleaseee helpp im giving a lot of points if corrected
    7·1 answer
  • Jordan gets paid to mow his neighbor's lawn. For every week that the mows the lawn, he earns $20. Write a rule as an algebraic e
    8·1 answer
  • A warehouse contains 55 boxes. Then a truck delivers a number of boxes at 12:00 p.m. and the team begins to unload them immediat
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!