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A grocer has 400 pounds of coffee in stock, 20 percent
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Updated on: 25 Jul 2014, 23:06
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A grocer has 400 pounds of coffee in stock, 20 percent of which is decaffeinated. If the grocer buys another 100 pounds of coffee of which 60 percent is decaffeinated, what percent, by weight, of the grocer’s stock of coffee is decaffeinated? A. 28% B. 30% C. 32% D. 34% E. 40%
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Originally posted by kanusha on 25 Jul 2014, 22:51.
Last edited by Gnpth on 25 Jul 2014, 23:06, edited 2 times in total.
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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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25 Jul 2014, 22:54
1 , 20% of 400 mean 320 , Next 60% of 100 mean 40 … so on total 360 is the coffee Out of total 500 pounds of coffee. 500 is 100% , 360 pounds = ?%..... 3600/500 = 72% is Original it mean 28%is Decaffeinated. So A 2, Using multipliers… 20% mean 0.2 60% mean 0.6 …. So multiplying both the multipliers 0.12 ?? Can anyone solve this using multipliers as approach?
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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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27 Jul 2014, 04:45
1. 20% of 400=80 pounds of decaffeinated coffee 2. 60% of 100=60 pounds of decaffeinated coffee 3. Wt have 140 pounds of decaffeinated out of 500 pounds, that means 140/500*100%=28%. The correct answer is A.
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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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27 Jul 2014, 04:47
kanusha wrote: 1 , 20% of 400 mean 320 , Next 60% of 100 mean 40 … so on total 360 is the coffee Out of total 500 pounds of coffee. 500 is 100% , 360 pounds = ?%..... 3600/500 = 72% is Original it mean 28%is Decaffeinated. So A 2, Using multipliers… 20% mean 0.2 60% mean 0.6 …. So multiplying both the multipliers 0.12 ??
Can anyone solve this using multipliers as approach? Kanusha, never mix percents if you take them from different numbers! In this case decaffeinated coffee= 0.2*400+0.6*100=140. So, again 140/500*100%=28%.
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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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20 Dec 2017, 12:28
kanusha wrote: A grocer has 400 pounds of coffee in stock, 20 percent of which is decaffeinated. If the grocer buys another 100 pounds of coffee of which 60 percent is decaffeinated, what percent, by weight, of the grocer’s stock of coffee is decaffeinated?
A. 28% B. 30% C. 32% D. 34% E. 40% Since the grocer has 400 pounds of coffee in stock, 20 percent of which is decaffeinated, 0.2 x 400 = 80 pounds are decaffeinated. Since the grocer buys another 100 pounds of coffee, 60 percent of which is decaffeinated, the grocer has 60 more pounds of decaffeinated coffee. Thus, the percentage of decaffeinated coffee is (80 + 60)/(400 + 100) = 140/500 = 28/100 = 28%. Answer: A
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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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20 Dec 2017, 12:55
This can be thought of in terms of weighted averages.
the initial coffee is 400 pounds and the latter coffee is 100 pounds so the first gets a weight of 4/5 and the latter gets a weight of 1/5.
20(4/5)+60(1/5)=
16+12=
28



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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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27 Dec 2017, 14:29
Alternate method: Alligation method 400 pounds (20%) 100 Pounds (60%) {qty 4:1} {Difference in ratio is 6020=40% ==> Concentration will be in reverse ratio ==> 1:4 ==> 1/5*40=8 or 4/5*40=32} Answer : 20+8 or 6032 = 28%
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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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15 Oct 2018, 12:12
20% of 400 is decaf
20% * 400 = 80
60% of 100 is decaf
60% * 100 = 60
(80 + 60) = 140
Total pounds of coffee = 400 + 100 = 500
\(\frac{140}{500}\) (multiply both by 2 to make easier to deal with as a percentage) = \(\frac{28}{100}\) = 28%
Answer choice A



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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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05 Jan 2019, 01:33
20% of 400 is decaffeinated
20% * 400 = 80
60% of 100 is decaffeinated
60% * 100 = 60
(80 + 60) = 140
Total pounds of coffee = 400 + 100 = 500
500 * decaffeinated / 100 = 140 5 * decaffeinated = 140 decaffeinated = 28 %
Answer choice A



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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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27 Aug 2019, 03:57
kanusha wrote: A grocer has 400 pounds of coffee in stock, 20 percent of which is decaffeinated. If the grocer buys another 100 pounds of coffee of which 60 percent is decaffeinated, what percent, by weight, of the grocer’s stock of coffee is decaffeinated?
A. 28% B. 30% C. 32% D. 34% E. 40% Dear VeritasKarishmaHow can I apply the concentration method here? I tried but fails. I hope you can help please. Thanks in advance



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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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28 Aug 2019, 04:27
kanusha wrote: A grocer has 400 pounds of coffee in stock, 20 percent of which is decaffeinated. If the grocer buys another 100 pounds of coffee of which 60 percent is decaffeinated, what percent, by weight, of the grocer’s stock of coffee is decaffeinated?
A. 28% B. 30% C. 32% D. 34% E. 40% It is a weighted average problem. Concentration of decaf in original inventory = 20% Concentration of decaf in new inventory = 60% Concentration of decaf in mix = ? w1/w2 = (A2  Aavg)/(Aavg  A1) 400/100 = (60  Aavg)/(Aavg  20) 4*Aavg  80 = 60  Aavg Aavg = 28% Answer (A) Check here: https://www.veritasprep.com/blog/2011/0 ... mixtures/
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Re: A grocer has 400 pounds of coffee in stock, 20 percent
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28 Aug 2019, 04:31
VeritasKarishma wrote: kanusha wrote: A grocer has 400 pounds of coffee in stock, 20 percent of which is decaffeinated. If the grocer buys another 100 pounds of coffee of which 60 percent is decaffeinated, what percent, by weight, of the grocer’s stock of coffee is decaffeinated?
A. 28% B. 30% C. 32% D. 34% E. 40% It is a weighted average problem. Concentration of decaf in original inventory = 20% Concentration of decaf in new inventory = 60% Concentration of decaf in mix = ? w1/w2 = (A2  Aavg)/(Aavg  A1) 400/100 = (60  Aavg)/(Aavg  20) 4*Aavg  80 = 60  Aavg Aavg = 28% Answer (A) Check here: https://www.veritasprep.com/blog/2011/0 ... mixtures/Thanks VeritasKarishma for your keen reply and response. But can I apply the following formula for the problem at hand: c1 * v1 = c2 * v2 Thanks




Re: A grocer has 400 pounds of coffee in stock, 20 percent
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