Let W1 be the initial weight of the solution.
Let S be the weight of salt in the solution.
Let W water1 be the initial weight of water in the solution.
Initially, the solution is 2% salt by weight.
So, S = 0.02 × W1
The rest is water, so W water1 = W1 − S = W1 − 0.02 W1 =0.98 W1
Now, more water is added. Let "W added" be the weight of water added.
The weight of salt remains the same.
Let "W2" be the final weight of the solution.
W2 =W1 +W added
The salt concentration decreases to 1% by weight.
So, S=0.01×W2
We have two expressions for S:
0.02 W1 =0.01 W2
Divide by 0.01:
2 W1 = W2
This means the final weight of the solution is twice the initial weight of the solution.
Now, let W water2 be the final weight of water in the solution.
W water2 = W2 −S.
Substitute W2 = 2 W1 : W water2 =2 W1 −S.
Since S=0.02 W1 :
W water2 = 2 W1 −0.02 W1 =1.98 W1
We need to find the ratio of the final weight of water to the initial weight of water in the solution:
W water2/ W water1
We have W water2 =1.98 W1 and W water1 = 0.98 W1
W water2/ W water1 =1.98 W1/ 0.98 W1 = 1.98/0.98
To simplify the fraction, multiply the numerator and denominator by 100:
98/198
Divide both by 2:
49/99The ratio of the final weight of water to the initial weight of water is 99:49.
The final answer is D.