Question 1197437
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Follow the formal algebraic solution shown in the response from the other tutor to see how they end up with the result that the amount of 60% alcohol solution is 11/20 of the total of 400kg.<br>
That result can be obtained much more quickly and easily without algebra by looking at the three percentages 40, 51, and 60 on a number line and observing that 51 is 11/20 of the way from 40 to 60.  That immediately gives you the result that 11/20 of the mixture is the 60% alcohol solution.<br>
ANSWER: 11/20 of 400kg, or 220kg, of the 60% solution; the other 180kg of the 40% solution.<br>