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.

Counting Numbers -1

Expert replies
by GmatKiss » Sat May 19, 2012 1:04 pm
1) Of the three-digit integers greater than 600, how many have two digits that are equal to each other and the remaining digit different from the other two?

(A) 120
(B) 116
(C) 108
(D) 107
(E) 72
Join the discussion
Source: — Problem Solving |

by neelgandham » Sat May 19, 2012 1:26 pm
Total number of three-digit numbers greater than 600 = 399.

Total number of three-digit numbers greater than 600 and with all distinct digits = 4*9*8 = 288. (First digit can take 4 values: 6, 7, 8 or 9, and the second digit can take 9 values and third digit can take 8 values.

Total number of Numbers greater than 600 and with all digits the same = 4 (666, 777, 888, 999).

Total number of Numbers with two digits equal to each other and the remaining digit different from the other two = Total number of three-digit numbers greater than 600 - Total number of three-digit numbers greater than 600 and with all distinct digits - Total number of Numbers greater than 600 and with all digits the same

Total number of Numbers with two digits equal to each other and the remaining digit different from the other two = 399-288-4=107.

Answer: D.
Anil Gandham
Welcome to BEATtheGMAT | Photography | Getting Started | BTG Community rules | MBA Watch
Check out GMAT Prep Now's online course at https://www.gmatprepnow.com/
Join the discussion

by kullayappayenugula » Mon May 21, 2012 8:57 pm
hi Neelgandham,

I have a doubt regarding the foramtion of "three-digit numbers greater than 600 and with all distinct digits"

it is given as 4*9*8 = 288. But this includes numbers like 661,662,663,.....771,772,... etc.

can you please tell me what is wrong in my understanding here.
Join the discussion

by Stuart@KaplanGMAT » Mon May 21, 2012 9:22 pm
kullayappayenugula wrote:hi Neelgandham,

I have a doubt regarding the foramtion of "three-digit numbers greater than 600 and with all distinct digits"

it is given as 4*9*8 = 288. But this includes numbers like 661,662,663,.....771,772,... etc.

can you please tell me what is wrong in my understanding here.
Hi!

Because you're multiplying by a smaller number, you've actually removed those duplicates.

Here's another way you could write the product:

(number of digits that could go in the first spot) * (number of digits that could go in the second spot that you haven't used yet) * (number of digits that could go in the third spot that you haven't used yet)

In the first spot, we have 6, 7, 8 and 9, for a total of 4 possible digits.
In the second spot, you have all 10 digits available (don't forget about 0); however, since you used one of them up in the first spot, there are only 9 digits left.
In the third spot, you have all 10 digits available; however, since you used one of them up in the first spot and a different one up in the second spot, there are only 8 digits left.

Accordingly, the number of non-digit repeating integers you can create is:

4*9*8 = 288
Image

Stuart Kovinsky | Kaplan GMAT Faculty | Toronto

Kaplan Exclusive: The Official Test Day Experience | Ready to Take a Free Practice Test? | Kaplan/Beat the GMAT Member Discount
BTG100 for $100 off a full course
Join the discussion