January 22, 2019 January 22, 2019 10:00 PM PST 11:00 PM PST In case you didn’t notice, we recently held the 1st ever GMAT game show and it was awesome! See who won a full GMAT course, and register to the next one. January 26, 2019 January 26, 2019 07:00 AM PST 09:00 AM PST Attend this webinar to learn how to leverage Meaning and Logic to solve the most challenging Sentence Correction Questions.
Author 
Message 
TAGS:

Hide Tags

Intern
Joined: 09 Jun 2014
Posts: 9
Concentration: Technology, Strategy

What is the greatest 6digit number when divided by?
[#permalink]
Show Tags
23 Jun 2015, 13:53
Question Stats:
81% (00:48) correct 19% (01:13) wrong based on 132 sessions
HideShow timer Statistics
What is the greatest 6digit number when divided by 6, 7 ,8 , 9, and 10 leaves a remainder of 4, 5, 6, 7, and 8 respectively? A. 456780 B. 678910 C. 997479 D. 997918 E. 997920
Official Answer and Stats are available only to registered users. Register/ Login.




GMAT Tutor
Joined: 24 Jun 2008
Posts: 1323

Re: What is the greatest 6digit number when divided by?
[#permalink]
Show Tags
23 Jun 2015, 15:00
When you divide a positive integer by 10, the remainder will just be the units digit. We know the remainder is 8 when we divide by 10, so D is the only possible answer. Or you could use the remainder by 9  if you want to know a large number's remainder when you divide by 9, you can sum its digits, and then take the remainder of that sum when you divide by 9. Only answer D gives you a sum of digits with a remainder of 7 when you divide the sum by 9.
_________________
GMAT Tutor in Toronto
If you are looking for online GMAT math tutoring, or if you are interested in buying my advanced Quant books and problem sets, please contact me at ianstewartgmat at gmail.com




Magoosh GMAT Instructor
Joined: 28 Dec 2011
Posts: 4485

Re: What is the greatest 6digit number when divided by?
[#permalink]
Show Tags
23 Jun 2015, 15:03
sandeepk123 wrote: What is the greatest 6digit number when divided by 6, 7 ,8 , 9, and 10 leaves a remainder of 4, 5, 6, 7, and 8 respectively?
A. 456780 B. 678910 C. 997479 D. 997918 E. 997920 Dear sandeepk123, I'm happy to respond. My friend, it is very hard to write truly GMATlike Quant questions. It's true that in a good GMAT question, it may look very complicated but involve an easy shortcut, as this one does. The shortcut here, though, is a bit too easy: the remainder when dividing by 10 has to be the units digit. Once one sees the shortcut, there is absolutely no work, and I imagine a large number of students will see this shortcut. My friend, I don't know if you are familiar with the idea of Item Response Theory. This is the science of what constitutes a truly high quality test question. The psychometricians who design the GMAT are experts in Item Response Theory. I only know a little about it myself. The gist is that a wellwritten question really strikes this delicate balance: many students find the question challenging, or are persuaded by incorrect trap answers, and only high performing students choose the correct answer. This question has an obvious right answer, but there is really no inducement for anyone, other than a blind guesser, to choose any of the other four answers. The questions would likely show similar performance among high performers and low performers. Thus, it is not an item that discriminates between users well. There are many layers involved in writing a truly GMATworthy math question. It's not just a matter of being clever with the math itself. Does all this make sense? Mike
_________________
Mike McGarry Magoosh Test Prep
Education is not the filling of a pail, but the lighting of a fire. — William Butler Yeats (1865 – 1939)



Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 6826
GPA: 3.82

Re: What is the greatest 6digit number when divided by?
[#permalink]
Show Tags
06 Apr 2017, 09:05
sandeepk123 wrote: What is the greatest 6digit number when divided by 6, 7 ,8 , 9, and 10 leaves a remainder of 4, 5, 6, 7, and 8 respectively?
A. 456780 B. 678910 C. 997479 D. 997918 E. 997920 There is a relation between divisors and remainder, which is remainders is 2 less than divisor, that is, remainder = divisor  2. And the answer should be a common multiple of ( 6, 7, 8, 9, 10 )  2 as follows. Let \(L\) be the \(LCM(6,7,8,9,10)\). Then \(L = 2^3 3^2 5^1 7^1 = 2520\). \(2,520 * 400  2,520 * 4 = 1,008,000  10,080 = 997,920\) Therefore, the answer is \(997,920  2 = 997,918\). The correct choice is D
_________________
MathRevolution: Finish GMAT Quant Section with 10 minutes to spare The oneandonly World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy. "Only $149 for 3 month Online Course" "Free Resources30 day online access & Diagnostic Test" "Unlimited Access to over 120 free video lessons  try it yourself"



Senior Manager
Joined: 22 Feb 2018
Posts: 416

Re: What is the greatest 6digit number when divided by?
[#permalink]
Show Tags
16 Oct 2018, 07:55
sandeepk123 wrote: What is the greatest 6digit number when divided by 6, 7 ,8 , 9, and 10 leaves a remainder of 4, 5, 6, 7, and 8 respectively?
A. 456780 B. 678910 C. 997479 D. 997918 E. 997920 OA: DOptions A, B and E are divisible by 10 i.e remainder is Zero. C gives a remainder of 9 when divided by 10. Only D gives a remainder of 8 when divided by 10.
_________________
Good, good Let the kudos flow through you




Re: What is the greatest 6digit number when divided by? &nbs
[#permalink]
16 Oct 2018, 07:55






