A man buys three kinds of batteries for his expedition adventure from a supply store. One of the batteries cost Rs. 5 each; the other costs cost Rs. 3 each and the third one costs just Rs. 0.5 each piece.
He buys a total of 100 batteries costing him Rs 100. How many of each do you think he buy?
Let us denote the chocolates with p, q and r.
We can frame the following two equations now
p + q + r = 100 ------ (1) 5p + 3q + 0.5r = 100 or 10p + 6q + r = 200 ---- (2) Now, 2*[(Eq. 2) - (Eq.1)] 9p + 5q = 100 from this equation'p' should be a multiple of 5 for p = 5 ; q = 11 for p = 10 ; q = 2 for p = 15 or more q becomes -ve Therefore, the two possible answers are p = 5, q = 11, r = 84 p = 10, q = 2, r = 88