Juice A contains 60% orange juice, 20% apple juice and 20% carrot

Question

Juice A contains 60% orange juice, 20% apple juice and 20% carrot juice. Juice B contains 20% orange juice and 80% carrot juice. If a juice concoction is made such that it contains 50% carrot juice, how much juice A is added as a percentage of the juice concoction?

A. 20
B. 30
C. 40
D. 50
E. 60

A. 20
B. 30
C. 40
D. 50
E. 60

divyadna · Answer

Let 100 mL concoction be made by mixing 'x' mL of juice A and (100-x) mL of juice B.

(20*x/100)+(100-x)(80/100)= 50
0.2x+80-0.8x=50
80-50= 0.6 x
x= 30/0.6= 50 mL
juice A added as a percentage of the juice concoction= 50*100/100= 50%
Option D is the answer

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G-Man · Answer

This is a weighted average question (What portion of 20%C juice should be mixed with 80%C juice to get 50%C juice)
Using the rule of alligation

20 80
 50
30 30

that is parts of Juice A to Parts of juice B = 30/30 = 1/1
In total 2 parts of solution, 1 part of Juice A and 1 part of Juice B are there
so 50% each.

SaquibHGMATWhiz · Answer

Solution:

Let us assume the concentration of juice A in the concoction be  x\%  
 So, the concentration of juice B in the concoction will be  (100-x)\%

Concentration of carrot juice in juice A and juice B are 20% and 80% 
 Concentration of carrot juice in the final concoction is 50% 
 So, according to the weighted average, we can say  50=\frac{20	imes x+80	imes (100-x)}{x+100-x} 
 ⇒50=\frac{20x+8000-80x}{100} 
 ⇒5000=-60x+8000 
 ⇒60x=3000 
 ⇒x=\frac{3000}{60} 
 ⇒x=50\%

Hence the right answer is    Option D

sristiiiiiiiii · Answer

20x/100 + 80x/100 = 50/100

x = 50/100 x 100

Solve it further - ans 50%

bumpbot · Answer

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Juice A contains 60% orange juice, 20% apple juice and 20% carrot

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Juice A contains 60% orange juice, 20% apple juice and 20% carrot

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