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A retailer orders u units of an item for which he pays d dol
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A retailer orders u units of an item for which he pays d dollars. However, he mistakenly receives u  3 items. How much was he overcharged, in terms of d and u? A. 3d  u B. 3du  9 C. (3d)/u D. (u−d)/3 E. (du)/3
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Originally posted by emmak on 11 Mar 2013, 23:38.
Last edited by Bunuel on 12 Mar 2013, 01:55, edited 1 time in total.
Edited the question.



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Re: A retailer orders u units of an item for which he pays d dol
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Re: A retailer orders u units of an item for which he pays d dol
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14 Mar 2013, 01:55
Bunuel wrote: emmak wrote: A retailer orders u units of an item for which he pays d dollars. However, he mistakenly receives u  3 items. How much was he overcharged, in terms of d and u?
A. 3d  u B. 3du  9 C. (3d)/u D. (u−d)/3 E. (du)/3 Say the retailer ordered u = 4 items for d = 4$ (1$ per item). Thus: He received 4  3 = 1 unit for 4$, which is 3$ more than the item actually costs. Now, plug u = 4 and d = 4 into the answer choices to see which one yields 3. Only C fits: (3d)/u = (3*4)/4 = 3. Answer: C. Hope it's clear. Please help me understand where am i going wrong .. Amount per items actually recieved = d/u3 Amount per items to be recieved = d/u Overcharged amount = d/u3  d/u = 3d/u(u3)



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Re: A retailer orders u units of an item for which he pays d dol
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14 Mar 2013, 02:07
akshaychandna wrote: Bunuel wrote: emmak wrote: A retailer orders u units of an item for which he pays d dollars. However, he mistakenly receives u  3 items. How much was he overcharged, in terms of d and u?
A. 3d  u B. 3du  9 C. (3d)/u D. (u−d)/3 E. (du)/3 Say the retailer ordered u = 4 items for d = 4$ (1$ per item). Thus: He received 4  3 = 1 unit for 4$, which is 3$ more than the item actually costs. Now, plug u = 4 and d = 4 into the answer choices to see which one yields 3. Only C fits: (3d)/u = (3*4)/4 = 3. Answer: C. Hope it's clear. Please help me understand where am i going wrong .. Amount per items actually recieved = d/u3 Amount per items to be recieved = d/u Overcharged amount = d/u3  d/u = 3d/u(u3) The retailer received u  3 items for the price of u items . The price of u items is d dollars (so, the price of an items d/u dollars); The price of u  3 items is d/u*(u 3) dollars; The difference is d  d/u*(u 3) = (du  du +3d)/u = 3d/u. Answer: C. Hope it helps.
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Re: A retailer orders u units of an item for which he pays d dol
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14 Mar 2013, 03:17
emmak wrote: A retailer orders u units of an item for which he pays d dollars. However, he mistakenly receives u  3 items. How much was he overcharged, in terms of d and u?
A. 3d  u B. 3du  9 C. (3d)/u D. (u−d)/3 E. (du)/3 Algebraic Solution Amount overcharged = Amount paid by him  Amount he should have paid Amount he should have paid= original price of items*total items purchased \(\frac{d}{u}*(u3)\) Amount paid by him was d dollars Thus amount overcharged = \( dd*\frac{(u3)}{u}\) On solving we get 3d/u Thus C



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Re: A retailer orders u units of an item for which he pays d dol
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02 Oct 2014, 02:05
Price ............. Quantity ............ Total \(\frac{d}{u}\) .................... u .................... d \(\frac{d}{u}\) ...................... (u3) ............... \(d  \frac{3d}{u}\) (Three pieces less received) \(Overcharge = d  d + \frac{3d}{u} = \frac{3d}{u}\) Answer = C
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Re: A retailer orders u units of an item for which he pays d dol
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11 Jan 2018, 10:54
BunuelI am making a silly mistake! can't put my finger on it! can you please tell me? I plugged in 10 for u and 10 for d. 10u=10d so 1u= 1d 103=7 7u = 10d so 1u=10/7d 1d 107d= 3/7 which is wrong! i cant figure out what am i doing wrong! Thanks



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A retailer orders u units of an item for which he pays d dol
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11 Jan 2018, 13:31
Please help me understand where am i going wrong .. Amount per items actually recieved = d/u3 Amount per items to be recieved = d/u Overcharged amount = d/u3  d/u = 3d/u(u3)[/quote] The retailer received u  3 items for the price of u items . The price of u items is d dollars (so, the price of an items d/u dollars); The price of u  3 items is d/u*(u 3) dollars; The difference is d  d/u*(u 3) = (du  du +3d)/u = 3d/u. Answer: C. Hope it helps.[/quote] Hi Bunuel can you explain how from this d  d/u*(u 3) you got this (du  du +3d)/u and this 3d/u ?
btw any nice link to know better how to simplify such algebraic expressions ? I always experience such technical issues with algebra
I know this time you gonna reply thanks!
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Re: A retailer orders u units of an item for which he pays d dol
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11 Jan 2018, 20:39
srishti201996 wrote: A retailer orders u units of an item for which he pays d dollars. However, he mistakenly receives u  3 items. How much was he overcharged, in terms of d and u? A. 3d  u B. 3du  9 C. (3d)/u D. (u−d)/3 E. (du)/3 BunuelI am making a silly mistake! can't put my finger on it! can you please tell me? I plugged in 10 for u and 10 for d. 10u=10d so 1u= 1d 103=7 7u = 10d so 1u=10/7d 1d 107d= 3/7 which is wrong! i cant figure out what am i doing wrong! Thanks The retailer ordered u = 10 items for d = 10$ (1$ per item). Thus: He received 10  3 = 7 unit for 10$, which is 3$ more than the items actually costs. Now, plug u = 10 and d = 10 into the answer choices to see which one yields 3. Only C fits: (3d)/u = (3*10)/10 = 3. Answer: C.
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Re: A retailer orders u units of an item for which he pays d dol
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Re: A retailer orders u units of an item for which he pays d dol
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12 Jan 2018, 08:52
Bunuel wrote: dave13 wrote: Please help me understand where am i going wrong ..
Amount per items actually recieved = d/u3
Amount per items to be recieved = d/u
Overcharged amount = d/u3  d/u = 3d/u(u3) The retailer received u  3 items for the price of u items . The price of u items is d dollars (so, the price of an items d/u dollars); The price of u  3 items is d/u*(u 3) dollars; The difference is d  d/u*(u 3) = (du  du +3d)/u = 3d/u. Answer: C. Hope it helps. Hi Bunuel can you explain how from this d  d/u*(u 3) you got this (du  du +3d)/u and this 3d/u ?
btw any nice link to know better how to simplify such algebraic expressions ? :) I always experience such technical issues with algebra :)
I know this time you gonna reply :) thanks! [/quote] http://www.themathpage.com/ARITH/addfr ... ions1.htm[/quote] Hello Bunuel ! Hope you have an amazing day! :) Thank you for the link, i reviewed the information provided in the website but I still do have doubts. Ok So we have this: \(d\)  \(\frac{d}{u}\)*\((u 3)\) First step: multiply \(\frac{d}{u}\) by \((u 3)\) > d + d3 < so here when we multiply \(\frac{d}{u}\) by \(U\)  U cancel out Now we have d d + d3 So where am i wrong Bunuel ? Many thanks for your methodical explanation !
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Re: A retailer orders u units of an item for which he pays d dol
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12 Jan 2018, 09:03
dave13 wrote: Bunuel wrote: dave13 wrote: Please help me understand where am i going wrong ..
Amount per items actually recieved = d/u3
Amount per items to be recieved = d/u
Overcharged amount = d/u3  d/u = 3d/u(u3) The retailer received u  3 items for the price of u items . The price of u items is d dollars (so, the price of an items d/u dollars); The price of u  3 items is d/u*(u 3) dollars; The difference is d  d/u*(u 3) = (du  du +3d)/u = 3d/u. Answer: C. Hope it helps. Hi Bunuel can you explain how from this d  d/u*(u 3) you got this (du  du +3d)/u and this 3d/u ?
btw any nice link to know better how to simplify such algebraic expressions ? I always experience such technical issues with algebra
I know this time you gonna reply thanks! http://www.themathpage.com/ARITH/addfr ... ions1.htm[/quote] Hello Bunuel ! Hope you have an amazing day! Thank you for the link, i reviewed the information provided in the website but I still do have doubts. Ok So we have this: \(d\)  \(\frac{d}{u}\)*\((u 3)\) First step: multiply \(\frac{d}{u}\) by \((u 3)\) > d + d3 < so here when we multiply \(\frac{d}{u}\) by \(U\)  U cancel out Now we have d d + d3 UPDATE: I got i forgot to multiplt d/u 3!!! i multiplied jusd D thinking that U canceled out! I am getting smarter lol [/quote]
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Re: A retailer orders u units of an item for which he pays d dol
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10 Aug 2018, 18:46
emmak wrote: A retailer orders u units of an item for which he pays d dollars. However, he mistakenly receives u  3 items. How much was he overcharged, in terms of d and u?
A. 3d  u B. 3du  9 C. (3d)/u D. (u−d)/3 E. (du)/3 Since the price per unit is d/u, the cost of u  3 units is d/u x (u  3) = (ud  3d)/u, so the retailer was overcharged by: d  (ud  3d)/u ud/u  (ud  3d)/u (ud  (ud  3d))/u (ud  ud + 3d)/u (3d)/u Answer: C
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Re: A retailer orders u units of an item for which he pays d dol
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11 Aug 2018, 06:29
emmak wrote: A retailer orders u units of an item for which he pays d dollars. However, he mistakenly receives u  3 items. How much was he overcharged, in terms of d and u?
A. 3d  u B. 3du  9 C. (3d)/u D. (u−d)/3 E. (du)/3 A retailer orders u units of an item for which he pays d dollars.So, EACH unit costs d/u dollars However, he mistakenly receives u  3 items.In other words, he received 3 fewer units than he wanted So, he paid for 3 units that he never received (i.e., he was overcharged for 3 units) How much was he overcharged, in terms of d and u?He was overcharged for 3 units, and EACH unit costs d/u dollars TOTAL overcharge = ( 3)( d/u) = 3d/u Answer: C Cheers, Brent
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