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Bunuel
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What am I doing wrong: say selling price is equal to $1 per book. 30 book is $30.

Cost per book assuming cost of 23 is equal to selling price. 30/23 = 1.3. 1.3x30 391.

30-39.1/30 =30.333
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What am I doing wrong: say selling price is equal to $1 per book. 30 book is $30.

Cost per book assuming cost of 23 is equal to selling price. 30/23 = 1.3. 1.3x30 391.

30-39.1/30 =30.333

For 1 quantity, if selling Price = 1

then cost Price would be\(= \frac{30}{23}\)

Loss = Cost Price - Selling Price

\(= \frac{30}{23} - 1\)

\(= \frac{7}{23}\)

\(\frac{7}{23}\) loss is achieved on CP of \(\frac{30}{23}\)

So, percentage loss would be

\(= \frac{\frac{7}{23}}{\frac{30}{23}} * 100\)

\(=\frac{7}{23} * \frac{23}{30} * 100\)

\(= \frac{700}{30}\)

\(= 23 \frac{1}{3}% Loss\)
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Bunuel
If C.P. of 23 books is equal to S.P of 30 books, then your gain or loss is ?

a) 23 \(\frac{1}{3}\) gain %

b) 30 \(\frac{10}{23}\) loss %

c) 23 \(\frac{1}{3}\) loss %

d) 30 \(\frac{1}{3}\) loss %

e) 40 \(\frac{1}{3}\) loss %

Say the cost price of 23 books is $23 so $1 for a book.

The cost of 30 books would be $30, and the selling price of 30 books would be 23$, hence the loss = ($30 - $23)/$30 = ~23.3%.

Answer: C.
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Bunuel
If C.P. of 23 books is equal to S.P of 30 books, then your gain or loss is ?

a) 23 \(\frac{1}{3}\) gain %

b) 30 \(\frac{10}{23}\) loss %

c) 23 \(\frac{1}{3}\) loss %

d) 30 \(\frac{1}{3}\) loss %

e) 40 \(\frac{1}{3}\) loss %

Let CP of 23 book = SP of 30 Books = 690

So, CP of 1 book is 30 & SP of 1 book is 23

Thus Loss % \(= \frac{( 30 - 23 )}{30}*100\)

Or, Loss % \(= \frac{7}{30}*100\)

Or, Loss % \(=23 \frac{1}{3}\)%

Hence, answer will be (C)
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Bunuel
If C.P. of 23 books is equal to S.P of 30 books, then your gain or loss is ?

a) 23 \(\frac{1}{3}\) gain %

b) 30 \(\frac{10}{23}\) loss %

c) 23 \(\frac{1}{3}\) loss %

d) 30 \(\frac{1}{3}\) loss %

e) 40 \(\frac{1}{3}\) loss %

We are given that the cost of 23 books is equal to the revenue of 30 books. If we let the cost per book = c and the revenue per book = r, we have:

23c = 30r

c = 30r/23

Percentage profit = (r - c)/c x 100

(r - 30r/23)/30r/23 x 100

(23r/23 - 30r/23)/30r/23 x 100

(-7r/23)/30r/23 x 100

(-7r x 23)/(23 x 30r) x 100

-7/30 x 100 = -0.2333 x 100 = 23 ⅓ loss.

Answer: C
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Bunuel
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If C.P. of 23 books is equal to S.P of 30 books, then your gain or loss is ?

a) 23 \(\frac{1}{3}\) gain %

b) 30 \(\frac{10}{23}\) loss %

c) 23 \(\frac{1}{3}\) loss %

d) 30 \(\frac{1}{3}\) loss %

e) 40 \(\frac{1}{3}\) loss %

Say the cost price of 23 books is $23 so $1 for a book.

The cost of 30 books would be $30, and the selling price of 30 books would be 23$, hence the loss = ($30 - $23)/$30 = ~23.3%.



Hi, I saw the formula for Loss % = ( Loss/ C.P ) * 100
but you have taken SP in the above formula used in question....can you suggest me how to use which one?

Thanks
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Bunuel
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If C.P. of 23 books is equal to S.P of 30 books, then your gain or loss is ?

a) 23 \(\frac{1}{3}\) gain %

b) 30 \(\frac{10}{23}\) loss %

c) 23 \(\frac{1}{3}\) loss %

d) 30 \(\frac{1}{3}\) loss %

e) 40 \(\frac{1}{3}\) loss %

Say the cost price of 23 books is $23 so $1 for a book.

The cost of 30 books would be $30, and the selling price of 30 books would be 23$, hence the loss = ($30 - $23)/$30 = ~23.3%.



Hi, I saw the formula for Loss % = ( Loss/ C.P ) * 100
but you have taken SP in the above formula used in question....can you suggest me how to use which one?

Thanks

Where do you see that? Solutions above use the same formula you mention.
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We could also do this question as follows: (by taking ratio of CP : SP.. because if we have their ratio, we can easily answer with profit/loss %)

CP of 23 books = SP of 30 books
Or CP*23 = SP*30
Thus, CP/SP = 30/23

Now we have the ratio. We can take CP=30 and SP=23. So this is a loss of 7 over 30
Thus loss% = 7/30 * 100 = 70/3 % or 23 1/3% loss

Hence option C is answer
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shreyas
C.P. of 23 books is equal to S.P of 30 books

If CP of x items = SP of y items, and if x > y, then profit; if x < y, then loss.
%L= 100 * (y - x)/y = 100 * (7/30) = 23.33%

If C.P. of 30 books is equal to S.P of 23 books: %P = 100 * (x - y)/y = 100 *(7/23) = 30.4%
Hi, is this formula still valid if we are given "S.P. of x items = C.P. of y items" ?

Thanks.

Sent from my XT1663 using GMAT Club Forum mobile app
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Bunuel
If C.P. of 23 books is equal to S.P of 30 books, then your gain or loss is ?

a) 23 \(\frac{1}{3}\) gain %

b) 30 \(\frac{10}{23}\) loss %

c) 23 \(\frac{1}{3}\) loss %

d) 30 \(\frac{1}{3}\) loss %

e) 40 \(\frac{1}{3}\) loss %

Say the cost price of 23 books is $23 so $1 for a book.

The cost of 30 books would be $30, and the selling price of 30 books would be 23$, hence the loss = ($30 - $23)/$30 = ~23.3%.



Hi, I saw the formula for Loss % = ( Loss/ C.P ) * 100
but you have taken SP in the above formula used in question....can you suggest me how to use which one?

Thanks

Where do you see that? Solutions above use the same formula you mention.[/quote]


Sorry but Im bit confused in it....

if I bought 24 books then

The CP of 24 books will be 24$

and decided to sell few more books with those 24 books...So total 30 books
The SP of 30 books will be 24$

As mentioned in question.
The CP of 24 books is 24$ and we sold 30 books in 24$

if we would have sold those books in 30$ THEN we would be in no losss or gain(But we didnt do that)

then formula must use

Loss = 30-24 = 6
CP = 24 (this is the amount in which we bought 24 books)

loss % = (6/24) * 100

Please help
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goalMBA1990
shreyas
C.P. of 23 books is equal to S.P of 30 books

If CP of x items = SP of y items, and if x > y, then profit; if x < y, then loss.
%L= 100 * (y - x)/y = 100 * (7/30) = 23.33%

If C.P. of 30 books is equal to S.P of 23 books: %P = 100 * (x - y)/y = 100 *(7/23) = 30.4%
Hi, is this formula still valid if we are given "S.P. of x items = C.P. of y items" ?

Thanks.

Sent from my XT1663 using GMAT Club Forum mobile app
Can any expert please confirm and revert about the reverse condition ?

Sent from my XT1663 using GMAT Club Forum mobile app
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goalMBA1990
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shreyas
C.P. of 23 books is equal to S.P of 30 books

If CP of x items = SP of y items, and if x > y, then profit; if x < y, then loss.
%L= 100 * (y - x)/y = 100 * (7/30) = 23.33%

If C.P. of 30 books is equal to S.P of 23 books: %P = 100 * (x - y)/y = 100 *(7/23) = 30.4%
Hi, is this formula still valid if we are given "S.P. of x items = C.P. of y items" ?

Thanks.

Sent from my XT1663 using GMAT Club Forum mobile app
Can any expert please confirm and revert about the reverse condition ?

Sent from my XT1663 using GMAT Club Forum mobile app

Hi

Solving such a question is quite simple. All you have to do is take ratio.

So if you are given: SP of x items = CP of y items

Or SP*x = CP*y .. then we have: CP/SP = x/y ..
Ratio of CP/SP is x/y

If y > x then Profit % = (y-x)/x * 100
If y < x then Loss% = (x-y)/x * 100

You will notice that our base is always the value of CP ('x' here).. But in previous reverse condition, base was 'y'

Hope this helps
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Set
CP = 30
SP = 23

gives the same total amount = 690$

Loss is 7 out of 30 dollar.

7/30 = a little less than 25 %.
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cost 23 books= sell 30 books

sell-cost
(23/30) - (30/30) = - (7/30)

since it's asking for a percentage
- (7/30) *100 = - 23(1/3) % LOSS

LETTER C
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