We Have 171 Kg Rice Custing 7 Rs/kg.we Have Rice At 11 Rs/kg And 2 Rs/kg .then After Mixing 11 Rs/kg And 2 Rs/kg Rice. What Is Quantity Of 11 Rs/kg Rice?

A = 11 rs/kg rice
b = 2 rs/kg rice

11a= cost of 11 rs/kg rice
2b= cost of 2 rs/kg rice

a+b = 171
11a+ 2b = 7 x 171

solving above equation

a = 95 & b = 76