A merchant has 100 lbs of sugar, part of which he sells at 7% profit and the rest at 11% profit. He gains 10 % on the whole. Find how much is sold at 7% profit?
Answers
A) 70 lbs B) 40 lbs C) 25 lbs D) 50 lbs E) 60 lbs
These types ofweighted averagequestions can be solved in a variety of ways, so you can choose whichever method you find easiest/fastest. Here's another variation on the Weighted Average Formula:   A = # of pounds sold at 7% profit   B = # of pounds sold at 11% profit   A+B = 100 pounds   (.07A + .11B)/(A+B) = .10   .07A + .11B = .1A + .1B   .01B = .03A   1B = 3A   1/3 = A/B   So, for every 1 pounds of A, we have 3 pounds of B.   With 100 pounds total, we have 25 pounds of A and 75 pounds of B.   Option 25 lbs
<result>C</result>
A merchant has 100 lbs of sugar, part of which he sells at 7% profit and the rest at 11% profit. He gains 10 % on the whole. Find how much is sold at 7% profit?