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 →

Que: Find the number of trailing zeroes after the rightmost non-zero digit in the value of 30!

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 amFollowed by: 37 members
Location: Las Vegas, USA
Thanked: 19 times
by Max@Math Revolution » Mon Jul 12, 2021 10:30 pm

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty—

Que: Find the number of trailing zeroes after the rightmost non-zero digit in the value of 30!

A) 3
B) 6
C) 7
D) 10
E) 25
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
User avatar
Elite Legendary Member
Posts: 3991
Joined: Fri Jul 24, 2015 2:28 amFollowed by: 37 members
Location: Las Vegas, USA
Thanked: 19 times

Re: Que: Find the number of trailing zeroes after the rightmost non-zero digit in the value of 30!

by Max@Math Revolution » Tue Jul 13, 2021 8:47 pm
Solution: 30! = 30 * 29 * 28 *………. * 3 * 2 * 1

When ‘5’ is multiplied by an even number, it results in ‘0’.

Numbers in 30! , which has ‘5’ as the factor are: 5, 10, 15, 20, 25, 30

25 will have ‘2’ (5’s). Hence, we have 7 ‘5’s’ and at least 7 even numbers in 30! , which when multiplied by 5 will result in ‘0’.

C is the correct answer.

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