Question

Sachin invested in national saving certificate scheme in the first year he invested rupees 5000 in the second year rupees 7000 in the third year rupees 9000 and so on find the total amount that he invested in 12 years

Answer 1

first we add all no. we get 21000
then we sub 12_3 we get 9
then we multiply 9×21000
819000