Jennifer can buy watches at a price of B dollars per watch, which she

Hey dave13

Unfortunately, this is wrong. I am not quite clear what you trying to do here

If you are assigning values B = $5(cost per watch).
She marks up the watches and sells for a total profit of T = $1
Assuming there is a N = 1 watch and she keeps a profit of 20%(which is 0.2*$5 = $1)

Now, working backward, trying to calculate the percentage by substituting the values
of B,N, and T, we will get

A. 100T/(NB) = 100/5 = 20 - Our solution is Option A(\(\frac{100T}{NB}\))

We don't need to substitute the values in the other 4 answer options as we have a match!

Hope that helps.

Let's say Jennifer marks up by x%

Total Profit = Marked up price of N watches - Cost of N watches

i.e. T = NB[1+(x/100)] - NB
i.e. (T) / NB = [(x/100)]
i.e. x = 100(T)/NB

Answer: Option

Let's say The price of each watch, i.e. B = 7,

Let's say Mark up = 400%==> 400% of 7 is 28, and the $7 watches are marked up $28,

then the selling price per watch = $35.

The profit per watch is $28, and so

if she sells N = 11 watches

Then Total profit, T = 28*11 = $308.

OK, now Substitute T = 308 = 11*28, N = 11, and B = 7, in options and hope to get 400 as our answer.

(A) 100T/(NB) = 100*11*28/(11*4) = 100*28/7 = 110*4 = 400 = works!

(B) TB/(100N) = 11*28*7/(100*11) = 28*7/100 = doesn’t work!

(C) 100TN/B = 100*11*28*11/7 = 100*11*4*11 = doesn’t work!

(D) ((T/N) – B)/(100B) = [(11*28/11) – 7]/(7*100) = (28 – 7)/(7*100) = 21/(7*100) = 3/100 = doesn’t work

(E) 100(T – NB)/N = 100(11*28 – 11*7)/7 = 100*11*21/7 = 100*11*3 = doesn’t work!

Answer: Option

Answer = A. 100T/(NB)

Cost price per watch = b

Selling price per watch = \(\frac{t}{n}\)

Let x = percent of the markup from her buy price to her sell price

\(x = 100 *\frac{t}{n} * \frac{1}{b} = \frac{100t}{nb}\)

MAGOOSH OFFICIAL SOLUTION

Algebraic Solution: If she makes a total profit of T for N watches, then that must be a profit of T/N for each watch. That must be the markup above cost on each watch, the amount of the increase. Well, percent increase = (amount of increase)/(starting amount) x 100% = (T/N)/B *100 = 100T/(NB)
Answer = (A)

That Algebraic solution was elegant if you saw it, but if not, here’s a full solution with picking numbers.

Numerical Solution: The price of each watch, I will pick B = 7, a prime number. For the percent increase, I will make this easy. Picking 100% is too easy, and too predictable, so I am going to pick 400% — 400% of 7 is 28, and the $7 watches are marked up $25, then the selling price is $35. The profit per watch is $28, and so if she sells N = 11 watches (another prime number), that would be a profit of T = 28*11 = $308. Leaving T in unmultiplied form will make it easier to cancel.

OK, now we will plug in T = 308 = 11*28, N = 11, and B = 7, and hope to get 400 as our answer.

(A) 100T/(NB) = 100*11*28/(11*4) = 100*28/7 = 110*4 = 400 = works!
(B) TB/(100N) = 11*28*7/(100*11) = 28*7/100 = doesn’t work!
(C) 100TN/B = 100*11*28*11/7 = 100*11*4*11 = doesn’t work!
(D) ((T/N) – B)/(100B) = [(11*28/11) – 7]/(7*100) = (28 – 7)/(7*100) = 21/(7*100) = 3/100 = doesn’t work
(E) 100(T – NB)/N = 100(11*28 – 11*7)/7 = 100*11*21/7 = 100*11*3 = doesn’t work!

We were lucky here. With one choice of numbers, we were able to eliminate four answer choices, leaving (A) as the only possible answer.

- See more at: https://magoosh.com/gmat/2014/gmat-pract ... QEkpA.dpuf

Cost price of one watch = B
Cost price of N watches = B*N

Total profit on N watches = T

Markup percentage = Profit/Cost Price *100 = T/BN * 100 = 100T/BN

Correct Option: A

let B be cost price of one watch
CP of N watches = NB
Profit = T = MP - NB (where MP= marked price)
profit % = (profit/CP)*100
= (T/NB)*100 =A

Hi, it looks like there are 2 NB's here - the one attached to the parantheses gets divided but what happened to the -NB on the far right?

let B be the cost +mark up price 2+1 = $3
T = total profit = $10t
N = total number of items sold

\(\frac{10t}{3b*n}\)

Hence, A

pushpitkc is my solution correct ?

Cost Price = B
No of items sold = N
Profit after selling N items = T ; Profit per item = \(\frac{T}{N}\)
Let "k" be the markup percentage , therefore selling price = \(\frac{(100+K)}{100} * B\)

We know ,
Selling Price - Cost Price = Profit
=> \(\frac{(100+K)}{100} * B - B = \frac{T}{N}\)
=> \(K = 100 (\frac{T}{NB} + \frac{B}{B}) - 100\)
=> \(K = 100(\frac{T}{NB})\)

The profit (or markup) per watch is T/N. So the markup is:

(T/N)/B x 100 = 100T/(NB)

percent of the purchase price.

Alternate Solution:

Jennifer’s profit per watch is T/N. Using the formula for profit, we can compute Jennifer’s sell price:

profit = sell price – buy price

T/N = sell price – B

T/N + B = sell price

We now use the percent markup formula:

% markup = (Sell price – Buy price) / Buy price x 100

% markup = (T/N + B – B) / B x 100

% markup = T/N / B x 100

% markup = T/BN x 100

% markup = 100T / (BN)

Answer: A

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