OEYou can write the given relationships as V : O = 2 : 3 and W : O = 5 : 7- ln order to combine both expressions into a single overall ratio, you first need to make sure that the common element in the two ratios (namely oil) appears as the same number in both ratios. The least common multiple of 3 and 7 is 21, so if you multiply the first ratio by 7 and the second ratio by 3, you can achieve your goal: V : O = 14 : 21 and W : O = 15 : 21, such that V : O : W : Total = 14:21 : 15: 50 (note that the 50 in the combined ratio is simply the sum of the preceding numbers.
You can now see that choice (A) is true: water to vinegar is in the ratio 15 : 14. Choice (B) is also correct: vinegar makes up 14/50=28% of the mixture.
Choice (C) is false, because 15/50=3/10 or 30% not 3/9 or 1/3
Finally, choice (D) is also correct because you can see that the item you consume the most of is oil. Therefore, given equal amounts to begin with, you will run out of oil the soonest.
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