profit and loss question

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profit and loss question

by hemant_rajput » Thu Jan 24, 2013 10:45 am
Q26. Divya goes to buy fruits and after a lot of bargaining is able to get the price of dozen apples reduced by 1 from the initial price, thereby enabling her to get 1 apple extra for ever Rupee saved(Getting no discount on the extra apple). What is the initial price of a dozen apples?
a. 10
b. 13
c. 12
d. 15
[spoiler]
oa:d[/spoiler]

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by Brent@GMATPrepNow » Thu Jan 24, 2013 10:51 am
hemant_rajput wrote:Q26. Divya goes to buy fruits and after a lot of bargaining is able to get the price of dozen apples reduced by 1 from the initial price, thereby enabling her to get 1 apple extra for ever Rupee saved(Getting no discount on the extra apple). What is the initial price of a dozen apples?
a. 10
b. 13
c. 12
d. 15
[spoiler]
oa:d[/spoiler]
So, there's no discount on any extra apples.
And, she can buy 1 extra apple for every 1 Rupee saved.
This tells me that each extra apple costs 1 Rupee (when there's no discount)

So, the initial price of 12 apples (before any discounts) must have been 12 Rupee.
Answer = C

In other words, the original price of the dozen apples was 12 Rupee. She bargained and got the price reduced by 1 Rupee (so the reduced price for the 12 apples was 11 Rupee). She then used this 1 Rupee to buy 1 extra apple.

Not sure how D is the official answer. Have I read/interpreted the question incorrectly?

Cheers,
Brent
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by hemant_rajput » Thu Jan 24, 2013 11:28 am
Brent@GMATPrepNow wrote:
hemant_rajput wrote:Q26. Divya goes to buy fruits and after a lot of bargaining is able to get the price of dozen apples reduced by 1 from the initial price, thereby enabling her to get 1 apple extra for ever Rupee saved(Getting no discount on the extra apple). What is the initial price of a dozen apples?
a. 10
b. 13
c. 12
d. 15
[spoiler]
oa:d[/spoiler]
So, there's no discount on any extra apples.
And, she can buy 1 extra apple for every 1 Rupee saved.
This tells me that each extra apple costs 1 Rupee (when there's no discount)

So, the initial price of 12 apples (before any discounts) must have been 12 Rupee.
Answer = C

In other words, the original price of the dozen apples was 12 Rupee. She bargained and got the price reduced by 1 Rupee (so the reduced price for the 12 apples was 11 Rupee). She then used this 1 Rupee to buy 1 extra apple.

Not sure how D is the official answer. Have I read/interpreted the question incorrectly?

Cheers,
Brent
Great, I was thinking I'm doing it incorrectly. I think the answer published in the book is wrong.
Please correct me if anyone has different understanding of the problem.

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by Fazze » Mon Feb 04, 2013 4:36 am
was kinda confused at first... could not finish the question in the 2-minute mark... however finally came up with a suitable equation...

price= "p"
real cost= 12 apples * "price p" = 12p
discounted cost= 12 apples * (p-1) = 12(p-1)

so,
=> real cost - discounted cost = an extra apple at price "p"
=> 12p - 12(p-1) = p
=> 12p - 12p + 12 = p
Therefore, p = 12.

is this okay ? to be honest i couldnt find the equation on the 1st try so i just tried the answer with all the given options... meaning i had input every option once to see if it works... is this what i should do everytime i get confused on making a proper equation in between the first 30 seconds just try out all the options?? please suggest...

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by Brent@GMATPrepNow » Mon Feb 04, 2013 8:24 am
Hey Fazze,

Your algebraic solution looks perfect.

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by viveksingh222 » Tue Feb 05, 2013 12:34 pm
Fazze wrote:was kinda confused at first... could not finish the question in the 2-minute mark... however finally came up with a suitable equation...

price= "p"
real cost= 12 apples * "price p" = 12p

discounted cost= 12 apples * (p-1) = 12(p-1)

so,
=> real cost - discounted cost = an extra apple at price "p"
=> 12p - 12(p-1) = p
=> 12p - 12p + 12 = p
Therefore, p = 12.

is this okay ? to be honest i couldnt find the equation on the 1st try so i just tried the answer with all the given options... meaning i had input every option once to see if it works... is this what i should do everytime i get confused on making a proper equation in between the first 30 seconds just try out all the options?? please suggest...
Hi Fazze..I didn't understand your approach..
you considered price per apple as p
last equation suggests that p=12
and as per my understanding the original cost(without discount) of the dozen apples must cost
12p= 12 * 12
and also according to the below equation of yours
discounted cost= 12 apples * (p-1) = 12(p-1)
doesn't this imply 12p-12 which implies it was Rs 12 , which was discounted from the dozen apple's price.
am I missing some point any where or is there any flaw in your approach..

Thank you,
Vivek.