BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

In the set of positive integers from 1 to 500, what is the sum of all the odd multiples of 5?

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 2898
Joined: Thu Sep 07, 2017 2:49 pmFollowed by: 5 members
Thanked: 6 times
by Vincen » Fri Jun 19, 2020 2:40 am

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty—

In the set of positive integers from 1 to 500, what is the sum of all the odd multiples of 5?

A. 10,000
B. 12,500
C. 17,500
D. 22,500
E. 25,000

[spoiler]OA=B[/spoiler]

Source: Magoosh
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Legendary Member
Posts: 2214
Joined: Fri Mar 02, 2018 2:22 pmFollowed by: 5 members

Re: In the set of positive integers from 1 to 500, what is the sum of all the odd multiples of 5?

by deloitte247 » Sat Jun 20, 2020 11:53 am
Odd multiples of 5 are in the sequence:
5, 15, 25, 35..........n with a common difference of 10
There are 500/5 = 100 multiples of 5 from 1 to 500 in which half are odd and half are even. Hence there are 50 odd multiples from 1 to 500

Therefore, the sequence of odd multiples of 5 from 1 to 500 =>
5, 15, 25, 35, 45, 55..................495
Where d = 10, a = 5, l = 495, and n = 50
$$Sum\ of\ all\ the\ 50\ terms\ =\frac{n\left(a+l\right)}{2}$$
$$=\frac{50\left(5+495\right)}{2}=25\cdot500$$
$$=12,500$$

Answer = B
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1