Products Selling by lucky draw scheme is legal or illegal

Dear sir good morning, I have registered a company and than I want to sale our retail products .for example hanky which cost is 10 rs. And I want to sale that product on 500 rs. Cost With sale tax and others marketing expensive. But I want to promote company product sale on behalf of lucky draw which scheme is if 5000 customers will purchase a hanky at the rate of 500 rs. Each.and all 5000 customers will participate in lucky draw and 45 lucky customers get 45 two wheels bikes. That is legal or illegal. Kindly suggest.