Answer: The law of demand states that the higher the price, the lower the quantity demanded and the lower the price, the higher the quantity demanded.
I wanted to buy a biro sometimes ago. The biro normally cost 50 Naira, I wanted to buy two biros for 100 naira. On getting to the shop, I was informed the biro now costs 30 naira. Due to the reduction in price, I bought 3 instead of 2.