Question

Bhagwanti inherited rs 12000. She invested part of it as 10% and the rest at 12%. Her annual income from these investments is rs 1280. How much did she invest at each rate?​

Answer 1

Let Rs.x was invested @10% and Rs.(12000−x) was invested @12%.

So by the problem

x×10%+(12000−x)×12%=1280

⇒12000×12%−x×2%=1280

⇒12000×12−x×2=128000

⇒2x=144000−128000=16000

⇒x=8000

So Rs.8000 was invested @10% and Rs.(12000−8000)=Rs.4000 was invested @12%.