How many liters of water must be evaporated from 50 liters of a 3 perc

Question

How many liters of water must be evaporated from 50 liters of a 3 percent sugar solution to get a 5 percent sugar solution?

A. 2 
B. 4
C. 6 
D. 10 
E. 20

BrainLab · Answer

3% sugar solution means that currently there are 1.5 Liters of sugar and this amount must be 5% of a reduced final amount (50-x)
1.5=0.05*(50-x)
0.05x=1
x=20
Asnwer E

CounterSniper · Answer

3% of sugar solution in 50 litres of water =1.5 litres
now that 1.5 litres is equal to 5% of some other solution.
which means
1.5=0.05X
x=150/5=30 Litres
thus litres of water to be evaporated =20

Vinayprajapati · Answer

How many liters of water must be evaporated from 50 liters of a 3 percent sugar solution to get a 5 percent sugar solution?

A. 2
B. 4
C. 6
D. 10
E. 20

Sugar ----------------- solution ----------------%sugar
3/100*50=1.5----------50----------------------3
1.5-----------------------50-x---------------------5

1.5/(50-x) =5/100
x=20
Hence E.

Thanks

gracie · Answer

let x=liters of water to be evaporated
(.97*50)-x=.95(50-x)
x=20 liters
E

generis · Answer

Water is zero percent sugar
Let x = amount of water evaporated

Weighted average approach:

(% sugar)(Vol) - (% sugar)(Vol) = (% sugar)(Vol)

Below, you don't have to write 0(x) on LHS, obviously.

0(x) is there to highlight that we  are  subtracting  x  amount of evaporating water, and water is zero percent sugar -- such that volume of (50 - x) on RHS makes more intuitive sense.

.03(50) - 0(x) = .05(50 - x) 
 1.5 = 2.5 - .05x 
 .05x = 1 
 x =\frac{1}{.05}=\frac{100}{5}= 20

Answer E

Paras96 · Answer

How many liters of water must be evaporated from 50 liters of a 3 percent sugar solution to get a 5 percent sugar solution?

The volume of water in 50 liters of a 3 percent sugar solution = 50*97% = 48.5 liter
The volume of sugar in 50 liters of a 3 percent sugar solution = 50*3% = 1.5 liter

On evaporation, the volume of water will decrease but the volume of sugar will be constant
For a 5 percent sugar solution, Let the total volume of the mixture be V
Therefore,   = 1.5
=> V = 30 litre
The volume of water = 28.5

Volume of water evaporated = 48.5 - 28.5 = 20

Hence E

Adnan123 · Answer

Concentration 1 * Volume 1 = Concentration 2 * Volume 2
3% * 50 = 5% * V2
Volume final = 30

50 - 30 = 20 liters of water must be evaporated

bumpbot · Answer

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How many liters of water must be evaporated from 50 liters of a 3 perc

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How many liters of water must be evaporated from 50 liters of a 3 perc

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