Multiple choice

700 ml of a mixture contains water and milk in the ratio 2:8. How much water must be added to the mixture so that the ratio of water and milk becomes 3:8?

  1. 70 ml

  2. 60 ml

  3. 65 ml

  4. 75 ml

  5. 43 ml
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A Correct answer
Explanation

Initial mixture: 700 ml, ratio 2:8 (water:milk). Water = 140 ml, Milk = 560 ml. We add x ml water: (140 + x) / 560 = 3 / 8. 8 * (140 + x) = 3 * 560 => 1120 + 8x = 1680 => 8x = 560 => x = 70 ml.

AI explanation

In the 700 ml mixture, the initial ratio of water to milk is 2 to 8, meaning there is one-fifth water and four-fifths milk; calculating the milk volume gives 0.8 multiplied by 700, which equals 560 ml. To achieve a new ratio of water to milk of 3 to 8 while keeping the 560 ml of milk constant, the required total water volume is three-eighths of 560, which equals 210 ml. Since the original mixture already contains 140 ml of water, the additional water needed is 210 minus 140, resulting in 70 ml.

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