Question

A certain type of mixture is prepared by mixing brand a at rs.9 a kg. with brand b at rs.4 a kg. ifthe mixture is worth rs.7 a kg., how many kgs. of brand a are needed to make 40kgs. of the mixture

Answer 1

A shopkeeper mixes 35 kg of wheat which cost him rs.15 per kg with 25 kg of wheat which cost him rs.20 per kg.he sells the mixture at rs.22 per kg.his gain is