/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 42 Find the sum of the first 80 pos... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Find the sum of the first 80 positive even integers.

Short Answer

Expert verified
The sum of the first 80 positive even integers is 6480.

Step by step solution

01

Identify the first term

The first positive even integer is \( 2 \), so the first term, \( a_1 \), is \( 2 \).
02

Identify the common difference

The difference between any two consecutive even numbers is \( 2 \), so the common difference \( d \) is \( 2 \). However, in this case, we don't need the common difference directly for our calculation, but it is useful for understanding the structure of the sequence.
03

Identify the 80th term

Since we know the first term \( a_1 \) and common difference \( d \), we can find the 80th term using the formula \( a_n = a_1 + (n-1)*d \). Here, \( n = 80 \), \( a_1 = 2 \), \( d = 2 \). Substituting these into the formula gives: \( a_{80} = 2 + (80-1)*2 =160 \). Thus, the 80th term, \( a_{80} \), is 160.
04

Find the sum

Now we have all we need to apply the formula for the sum of an arithmetic series: \( S_n = \frac{n}{2} (a_1 + a_n) \). Substituting the values: \( S_{80} = \frac{80}{2} (2 + 160) = 40 * 162 = 6480 \). Thus, the sum of the first 80 positive even integers is 6480.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Shown again is the table indicating the marital status of the U.S. population in 2010. Numbers in the table are expressed in millions. Use the data in the table to solve Exercises \(1-10 .\) Express probabilities as simplified fractions and as decimals rounded to the nearest hundredth $$ \begin{array}{llllll} {} & {} & {\text { Never}} \\ {} & {\text {Married}} & {\text { Married }} & {\text { Divorced }} & {\text { Widowed }} & {\text { Total }} \\ \hline \text { Male } & {65} & {40} & {10} & {3} & {118} \\ \hline \text { Female } & {65} & {34} & {14} & {11} & {124} \\ \hline \text { Total } & {130} & {74} & {24} & {14} & {242} \end{array} $$ If one person is randomly selected from the population described in the table, find the probability, expressed as a simplified fraction and as a decimal to the nearest hundredth, that the person $$\text {is divorced.}$$

Evaluate each expression. \(1-\frac{_{3} P_{2}}{_{4} P_{3}}\)

Fifty people purchase raffle tickets. Three winning tickets are selected at random. If first prize is \(\$ 1000,\) second prize is \(\$ 500,\) and third prize is \(\$ 100,\) in how many different ways can the prizes be awarded?

A medical researcher needs 6 people to test the effectiveness of an experimental drug. If 13 people have volunteered for the test, in how many ways can 6 people be selected?

On New Year's Eve, the probability of a person driving while intoxicated or having a driving accident is \(0.35 .\) If the probability of driving while intoxicated is 0.32 and the probability of having a driving accident is \(0.09,\) find the probability of a person having a driving accident while intoxicated.

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.