The cheapest product is always the most economical product because everybody want to buy the cheapest product always they think the cheaptest product is best price and economical product when they buy something they will check the price .
The cheapest product must sell low price or sell in economical price because the supply want to sell the product to everyone and everyone can use the product . In daily life the people want to use the product everyday so the supply make the product in low price.
The people want to buy the product in low price because they want to safe their money. And they think when they buy something that the thing is economical product for them .