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

Redeem

Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

★★★★★5.0559 reviews
GMATLiveTeach 7 seats left
Chris Peckover
NEXT LIVE COHORT

Oct 13 to Jan 7, 2027

with Chris Peckover

Schedule
Tue, Thu · 8:00 to 10:00 PM ET
Included
40 live hours + 6 months of GMAT OnDemand
  • Live instruction and real-time questions
  • Class recordings and assigned practice
View class & enroll
Limited cohort · enrollment openTarget Test Prep
EALiveTeach 5 seats left
Logan Thompson
EXECUTIVE ASSESSMENT

Sep 6 to Dec 6, 2026

with Logan Thompson

Schedule
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll
Limited cohort · enrollment openTarget Test Prep
GMATOnDemand Start anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions

Compare the format, schedule, and included access before enrolling. Prices and seat counts shown reflect the supplied offer details.

remainder problem

Expert replies
Source: — Problem Solving |

by Brent@GMATPrepNow » Sun Sep 25, 2016 7:02 am
aarzoo wrote:What is the remainder when 7^7 is divided by 19?
Ho do I solve this one?
Two questions:
1) Where are the 5 answer choices that always accompany GMAT questions?
2) What is the source of this question?

Unless I'm missing something, this question really isn't a GMAT-quality question, since it requires too much number crunching (e.g., looking for a pattern by finding the remainder when 7^2, 7^3 and 7^4 are divided by 19)

We could use some modular arithmetic (https://en.wikipedia.org/wiki/Modular_arithmetic) to solve this, but I believe this would be out of scope for the GMAT.


Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Join the discussion

by Matt@VeritasPrep » Thu Sep 29, 2016 7:26 pm
I'd use some smaller powers to help you.

7� = 7³ * 7³ * 7

Now look for powers of 19 close to these. 7³ = 343, and 19² = 361, so those are good candidates. Notice that 361 - 19 = 342, so 343 / 342 has remainder 1. Thus 7³ has remainder 1 by 19, and

7� = 7³ * 7³ * 7 = (remainder 1) * (remainder 1) * (remainder 7) = remainder 7.
Join the discussion