Author |
Message |
TAGS:
|
|
Director
Joined: 29 Nov 2012
Posts: 828
|
Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
Updated on: 05 Oct 2013, 04:27
14
This post was BOOKMARKED
D
E
Question Stats:
62% (02:24) correct 38% (02:31) wrong based on 177 sessions
HideShow timer Statistics
Sally has five red cards numbered 1 through 5 and four blue cards numbered 3 through 6. She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the numbers on the middle three cards? A. 8 B. 9 C. 10 D. 11 E. 12
Official Answer and Stats are available only to registered users. Register/ Login.
_________________
Click +1 Kudos if my post helped...
Amazing Free video explanation for all Quant questions from OG 13 and much more http://www.gmatquantum.com/og13th/
GMAT Prep software What if scenarios http://gmatclub.com/forum/gmat-prep-software-analysis-and-what-if-scenarios-146146.html
Originally posted by fozzzy on 05 Oct 2013, 04:08.
Last edited by Bunuel on 05 Oct 2013, 04:27, edited 2 times in total.
Edited the question.
|
|
|
Math Expert
Joined: 02 Sep 2009
Posts: 44636
|
Re: Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
05 Oct 2013, 04:26
5
This post received KUDOS
Expert's post
3
This post was BOOKMARKED
fozzzy wrote: Sally has five red cards numbered 1 through 5 and four blue cards numbered 3 through 6. She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the numbers on the middle three cards??
A) 8 B) 9 C) 10 D) 11 E) 12 The cards are stacked so that the colors alternate: R- B- R- B- R- B- R- B- R. We are also told that the number on each red card divides evenly into the number on each neighboring blue card. There are two primes in Blue cards: 3 and 5. Their divisors are 1 and 3 AND 1 and 5, respectively. Thus R1 must be between R3 and R5, R3 must be by B3 and R5 must be by B5: 3- 3- 1- 5- 5. Next, add multiple of 3 to the left of 3: 6- 3- 3- 1- 5- 5. Add factor of 6 to the left of 6: 2- 6- 3- 3- 1- 5- 5. Add multiple of 2 to the left of 2: 4- 2- 6- 3- 3- 1- 5- 5. And finally add factor of 4 to the left of 4: 4- 4- 2- 6- 3- 3- 1- 5- 5. The sum of the numbers on the middle three cards is 6+ 3+ 3=12. Answer: E. Hope it's clear.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
 What are GMAT Club Tests? Extra-hard Quant Tests with Brilliant Analytics
|
|
|
Intern
Joined: 23 Jul 2013
Posts: 20
|
Re: Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
17 Oct 2013, 00:10
Bunuel wrote: fozzzy wrote: Sally has five red cards numbered 1 through 5 and four blue cards numbered 3 through 6. She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the numbers on the middle three cards??
A) 8 B) 9 C) 10 D) 11 E) 12 The cards are stacked so that the colors alternate: R- B- R- B- R- B- R- B- R. We are also told that the number on each red card divides evenly into the number on each neighboring blue card. There are two primes in Blue cards: 3 and 5. Their divisors are 1 and 3 AND 1 and 5, respectively. Thus R1 must be between R3 and R5, R3 must be by B3 and R5 must be by B5: 3- 3- 1- 5- 5. Next, add multiple of 3 to the left of 3: 6- 3- 3- 1- 5- 5. Add factor of 6 to the left of 6: 2- 6- 3- 3- 1- 5- 5. Add multiple of 2 to the left of 2: 4- 2- 6- 3- 3- 1- 5- 5. And finally add factor of 4 to the left of 4: 4- 4- 2- 6- 3- 3- 1- 5- 5. The sum of the numbers on the middle three cards is 6+ 3+ 3=12. Answer: E. Hope it's clear. Hi Bunuel, Does such questions actualy appear on GMAT..?? its really tough and makes my mind wooof..!!
|
|
|
Math Expert
Joined: 02 Sep 2009
Posts: 44636
|
Re: Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
17 Oct 2013, 03:11
ishdeep18 wrote: Bunuel wrote: fozzzy wrote: Sally has five red cards numbered 1 through 5 and four blue cards numbered 3 through 6. She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the numbers on the middle three cards??
A) 8 B) 9 C) 10 D) 11 E) 12 The cards are stacked so that the colors alternate: R- B- R- B- R- B- R- B- R. We are also told that the number on each red card divides evenly into the number on each neighboring blue card. There are two primes in Blue cards: 3 and 5. Their divisors are 1 and 3 AND 1 and 5, respectively. Thus R1 must be between R3 and R5, R3 must be by B3 and R5 must be by B5: 3- 3- 1- 5- 5. Next, add multiple of 3 to the left of 3: 6- 3- 3- 1- 5- 5. Add factor of 6 to the left of 6: 2- 6- 3- 3- 1- 5- 5. Add multiple of 2 to the left of 2: 4- 2- 6- 3- 3- 1- 5- 5. And finally add factor of 4 to the left of 4: 4- 4- 2- 6- 3- 3- 1- 5- 5. The sum of the numbers on the middle three cards is 6+ 3+ 3=12. Answer: E. Hope it's clear. Hi Bunuel, Does such questions actualy appear on GMAT..?? its really tough and makes my mind wooof..!! Yes, the question is hard, though I think you can expect such questions if you are doing well on the test.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
 What are GMAT Club Tests? Extra-hard Quant Tests with Brilliant Analytics
|
|
|
Intern
Joined: 30 Sep 2013
Posts: 22
|
Re: Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
12 Mar 2014, 08:53
Bunuel wrote: fozzzy wrote: Sally has five red cards numbered 1 through 5 and four blue cards numbered 3 through 6. She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the numbers on the middle three cards??
A) 8 B) 9 C) 10 D) 11 E) 12 The cards are stacked so that the colors alternate: R- B- R- B- R- B- R- B- R. We are also told that the number on each red card divides evenly into the number on each neighboring blue card. There are two primes in Blue cards: 3 and 5. Their divisors are 1 and 3 AND 1 and 5, respectively. Thus R1 must be between R3 and R5, R3 must be by B3 and R5 must be by B5: 3- 3- 1- 5- 5. Next, add multiple of 3 to the left of 3: 6- 3- 3- 1- 5- 5. Add factor of 6 to the left of 6: 2- 6- 3- 3- 1- 5- 5. Add multiple of 2 to the left of 2: 4- 2- 6- 3- 3- 1- 5- 5. And finally add factor of 4 to the left of 4: 4- 4- 2- 6- 3- 3- 1- 5- 5. The sum of the numbers on the middle three cards is 6+ 3+ 3=12. Answer: E. Hope it's clear. Hi bunuel, I am not able to understand the logic behind the sequence. Why it can't be like this 2- 6- 3- 3- 4- 4- 1- 5- 5And have sum as 3+4+4 = 11 Or any other combination
|
|
|
Math Expert
Joined: 02 Sep 2009
Posts: 44636
|
Re: Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
12 Mar 2014, 09:30
riteshgmat wrote: Bunuel wrote: fozzzy wrote: Sally has five red cards numbered 1 through 5 and four blue cards numbered 3 through 6. She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the numbers on the middle three cards??
A) 8 B) 9 C) 10 D) 11 E) 12 The cards are stacked so that the colors alternate: R- B- R- B- R- B- R- B- R. We are also told that the number on each red card divides evenly into the number on each neighboring blue card. There are two primes in Blue cards: 3 and 5. Their divisors are 1 and 3 AND 1 and 5, respectively. Thus R1 must be between R3 and R5, R3 must be by B3 and R5 must be by B5: 3- 3- 1- 5- 5. Next, add multiple of 3 to the left of 3: 6- 3- 3- 1- 5- 5. Add factor of 6 to the left of 6: 2- 6- 3- 3- 1- 5- 5. Add multiple of 2 to the left of 2: 4- 2- 6- 3- 3- 1- 5- 5. And finally add factor of 4 to the left of 4: 4- 4- 2- 6- 3- 3- 1- 5- 5. The sum of the numbers on the middle three cards is 6+ 3+ 3=12. Answer: E. Hope it's clear. Hi bunuel, I am not able to understand the logic behind the sequence. Why it can't be like this 2- 6- 3- 3- 4- 4- 1- 5- 5And have sum as 3+4+4 = 11 Or any other combination Your sequence is not possible because it violates the condition that the number on each red card divides evenly into the number on each neighboring blue card. 2- 6- 3- 3- 4- 4- 1- 5- 5 --> 4 there is NOT a factor of neighboring 3. While in the following sequence 4- 4- 2- 6- 3- 3- 1- 5- 5 the number on EACH red card is a factor of EACH neighboring blue card. Hope it's clear.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
 What are GMAT Club Tests? Extra-hard Quant Tests with Brilliant Analytics
|
|
|
Manager
Joined: 04 Sep 2012
Posts: 99
Location: Philippines
Concentration: Marketing, Entrepreneurship
Schools: Ross (Michigan) - Class of 2017
GMAT 1: 620 Q48 V27 GMAT 2: 660 Q47 V34 GMAT 3: 700 Q47 V38
GPA: 3.25
WE: Sales (Manufacturing)
|
Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
30 Jul 2014, 02:06
1
This post received KUDOS
1
This post was BOOKMARKED
fozzzy wrote: Sally has five red cards numbered 1 through 5 and four blue cards numbered 3 through 6. She stacks the cards so that the colors alternate and so that the number on each red card divides evenly into the number on each neighboring blue card. What is the sum of the numbers on the middle three cards?
A. 8 B. 9 C. 10 D. 11 E. 12 1,2,3,4,53,4,5,6Rule states that the red card must be a multiple of the 2 blue cards next to it. Therefore, we should start off with the most multiple (6) 2- 6- 31,2,3,4,53,4,5,6We should then attempt to connect 2 & 3 with a multiple among the remaining red cards 4- 2- 6- 3- 31,2,3,4,53,4,5,6We then need to look for a factor of 4 & 3. 4- 4- 2- 6- 3- 3- 11,2,3,4,53,4,5,6Fill in missing Blue 5 & Red 5 on the far right side 4- 4- 2- 6- 3- 3- 1- 5- 5We are looking for the sum of the 3 middle digits. 4- 4- 2- 6-3-3- 1- 5- 56+3+3=12 Answer is E
|
|
|
Intern
Joined: 15 Oct 2017
Posts: 16
|
Re: Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
05 Dec 2017, 00:09
Why can't it be 3-3-6-2-4-4-1-5-5
Sum here equals 10.
|
|
|
Math Expert
Joined: 02 Sep 2009
Posts: 44636
|
Re: Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
05 Dec 2017, 00:13
|
|
|
Intern
Joined: 15 Oct 2017
Posts: 16
|
Re: Sally has five red cards numbered 1 through 5 and four blue [#permalink]
Show Tags
05 Dec 2017, 00:17
Got it. I got confused about the order. Thanks Bunuel Sent from my ONE A2003 using GMAT Club Forum mobile app
|
|
|
|
Re: Sally has five red cards numbered 1 through 5 and four blue
[#permalink]
05 Dec 2017, 00:17
|
|
|
|
|
|
|