gmatquant25 wrote:
In a LAB experiment, a 100 ml compound of element X and element Y needs to be increased to 120 ml by adding some quantity of element X, and some quantity of element Y. If the original compound contains 30% of element X, how much (in ml) of element Y must be added so that element X will be exactly one third of the resulting mixture ?
A. 40 ml
B. 100/3 ml
C. 20 ml
D. 20/3 ml
E. 10 ml
There are 0.3*100=30 ml of element X in the initial solution.
We need X to be 1/3rd of 120 ml in the resulting
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