Question

2. A man purchased 150 pens at the rate of 12 per pen. He sold 50 pens at a gain of 10%. At what gain per cent
must he sell the remaining pens, so as to gain 15% on the whole transaction?
12. Three items are purchased at 500 each. One of them is sold at a loss of 10%. At what price should the other
be sold, so as to gain 25% on the whole transaction? What is the gain % on these two items?​

Answer 1

this is the answer of ques 2

sorry mate i don't know the answer of ques 12