Rohit bought 10 packs of pens, which had 5 pens in one pack for Rs. 10 per pack and while selling them he packed them in 5 different pack of 10 pens each and sold them at Rs. 40 per pack. Find the total profit.
A pack of 350 stickers cost Rs 700, find the cost of
(a) 1 sticker
(b) 10 packs f stickers