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

Redeem

KEYE food drive

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
GMAT Instructor
Posts: 3650
Joined: Wed Jan 21, 2009 4:27 am
Location: India
Thanked: 267 times
Followed by:80 members
GMAT Score:760

KEYE food drive

by sanju09 » Thu Sep 09, 2010 4:58 am
KEYE food drive encourages grocery shoppers to donate to their local food bank by purchasing charity coupons worth $3 each or $7 each. Stacy, a shopper, purchased m charity coupons worth $3 each and n charity coupons worth $7 each towards the food drive and paid a total of $144 for the coupons. Which of the following cannot be m + n?
(A) 40
(B) 36
(C) 32
(D) 28
(E) 20

Source: [email protected]
Attachments
starving.jpg
The mind is everything. What you think you become. -Lord Buddha



Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001

www.manyagroup.com
Top
Source: — Problem Solving |
User avatar
Legendary Member
Posts: 659
Joined: Mon Dec 14, 2009 8:12 am
Thanked: 32 times
Followed by:3 members

by Gurpinder » Thu Sep 09, 2010 5:50 am
sanju09 wrote:KEYE food drive encourages grocery shoppers to donate to their local food bank by purchasing charity coupons worth $3 each or $7 each. Stacy, a shopper, purchased m charity coupons worth $3 each and n charity coupons worth $7 each towards the food drive and paid a total of $144 for the coupons. Which of the following cannot be m + n?
(A) 40
(B) 36
(C) 32
(D) 28
(E) 20

Source: [email protected]
(E) - 20
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.
Top
User avatar
GMAT Instructor
Posts: 3650
Joined: Wed Jan 21, 2009 4:27 am
Location: India
Thanked: 267 times
Followed by:80 members
GMAT Score:760

by sanju09 » Thu Sep 09, 2010 5:54 am
E is not -20, your explanation Gurpinder?
The mind is everything. What you think you become. -Lord Buddha



Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001

www.manyagroup.com
Top
User avatar
Legendary Member
Posts: 659
Joined: Mon Dec 14, 2009 8:12 am
Thanked: 32 times
Followed by:3 members

by Gurpinder » Thu Sep 09, 2010 6:02 am
sanju09 wrote:E is not -20, your explanation Gurpinder?
Oh, no no, I meant (E).

m --> $3 each
n --> $7 each


just to play around with the numbers, I tried to go for the lowest value of M+N. I can get the lowest value when I have fewer cupons. To have fewer coupons, I should have most of then the $7 ones and only the rest $3.

140/7=20

left with 4...... and 1 of the $3..... so I am still left with a $1 remaining.

This = 21 coupons with $1 remaining. If 21 doesent work out, there is not way you can get 20 (m+n).

That means that the total cannot be 20, so (E).

Does that make sense Sanju?
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.
Top
User avatar
GMAT Instructor
Posts: 3650
Joined: Wed Jan 21, 2009 4:27 am
Location: India
Thanked: 267 times
Followed by:80 members
GMAT Score:760

by sanju09 » Thu Sep 09, 2010 6:16 am
Gurpinder wrote:
sanju09 wrote:E is not -20, your explanation Gurpinder?
Oh, no no, I meant (E).

m --> $3 each
n --> $7 each


just to play around with the numbers, I tried to go for the lowest value of M+N. I can get the lowest value when I have fewer cupons. To have fewer coupons, I should have most of then the $7 ones and only the rest $3.

140/7=20

left with 4...... and 1 of the $3..... so I am still left with a $1 remaining.

This = 21 coupons with $1 remaining. If 21 doesent work out, there is not way you can get 20 (m+n).

That means that the total cannot be 20, so (E).

Does that make sense Sanju?
Have you ever tried to take a coin out from the right cross-pocket of the pant you're wearing, using your left hand, or vise versa? You did exactly that here, and did it to perfection as well. I would still love to see more approaches, mate.
The mind is everything. What you think you become. -Lord Buddha



Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001

www.manyagroup.com
Top
User avatar
Legendary Member
Posts: 659
Joined: Mon Dec 14, 2009 8:12 am
Thanked: 32 times
Followed by:3 members

by Gurpinder » Thu Sep 09, 2010 6:21 am
sanju09 wrote:
Gurpinder wrote:
sanju09 wrote:E is not -20, your explanation Gurpinder?
Oh, no no, I meant (E).

m --> $3 each
n --> $7 each


just to play around with the numbers, I tried to go for the lowest value of M+N. I can get the lowest value when I have fewer cupons. To have fewer coupons, I should have most of then the $7 ones and only the rest $3.

140/7=20

left with 4...... and 1 of the $3..... so I am still left with a $1 remaining.

This = 21 coupons with $1 remaining. If 21 doesent work out, there is not way you can get 20 (m+n).

That means that the total cannot be 20, so (E).

Does that make sense Sanju?
Have you ever tried to take a coin out from the right cross-pocket of the pant you're wearing, using your left hand, or vise versa? You did exactly that here, and did it to perfection as well. I would still love to see more approaches, mate.

yayy....... :D hahah
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.
Top
User avatar
Master | Next Rank: 500 Posts
Posts: 324
Joined: Mon Jul 05, 2010 6:44 am
Location: London
Thanked: 70 times
Followed by:3 members

by kmittal82 » Thu Sep 09, 2010 6:39 am
Very interesting question..

A closer look will reveal that the first set of numbers which will satisfy 144 is (3x41) + (7x3), next one is (3x34) + (7x6) and the one after is (3x27) + (7x9)... see the pattern? Multiple of 3 always decreases by 7, and multiple of 7 always increases by 3.

Using this information, 20 is not possible, hence (E)
Top
Post new topic Post Reply
• Page 1 of 1