Let's consider W the weight of the solution before adding water. Let's calculate the weight of water in each solution:
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weight of water in solution 1 (before adding water)
2% is the concentration of salt, therefore 98% is the concentration of water
--> weight of water in solution 1 = 0.98 * W
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weight of water in solution 2:
After adding a certain amount of water, let's call it x units, the weight becomes W+x, and the concentration of salt becomes 1%. So similarly, the concentration of water becomes 99%
--> weight of water in solution 2 = 0.99 * (W+x)
[ weight of water in solution 2 ][/ weight of water in solution 1 ] = [ 0.99 * (W+x) ][/ 0.98*W ]
Developing further:
[ weight of water in solution 2 ][/ weight of water in solution 1 ] = [ 99 * (1+x/W) ][/ 98 ]
The minimum value 1+x/W could take is 1, the resulting ratio would then be 100:98, which could be simplified to 50:49 --> Option B
Bunuel
A saline solution is 2% salt by weight, with the rest being water. After more water is added, the salt concentration decreases to 1% by weight. What is the ratio of the final weight of water to the initial weight of water in the solution?
A. 1:2
B. 50:49
C. 2:1
D. 99:49
E. 100:49