A man sells three articles A, B and C and gains 10% on A, 20% on B and looses 10% on C. He breaks even when combined selling prices of A and C are considered. He gains 5% when combined prices of B and C are considered. What is his net loss or gain on the sale of all the articles.
So suppose the buying cost of A, B, C are a,b,c respectively. Now since he breaks even with selling A and C we have $$1.1a+0.9b=a+b$$ Also from second condition $$1.2b+0.9c=1.05(b+c)$$ Now we want to compute x such that $$1.1a+1.2b+0.9c=x(a+b+c)$$ How do I do this? I'm sure there is a simple step here but I cant seem to get it!