A scientist needs a 10% saline solution for an experiment .In his closet ,he finds a 20 ounce bottle of 25% saline solution.How many ounces of pure water should he add to the mixture to produce the correct saline solution?
A. 30
B. 20
C. 15
D. 35
E. 25
সঠিক উত্তরঃ
A.
30
Explanation:

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