Question 820323
Steps to solve.
1) Find the radius r of the inner circle.
2) Find the radius R of the outer circle.
3) Find a formula for the outer circumference O .
4) Multiply O to give us the amount in rupees.

1) Use the formula for circumference C = (pi)(2r)
C = (pi)(2r)
divide each side by (pi)
C/(pi) = 2r
divide each side by 2
C/(2(pi)) = r

2) R, the outer radius = r + 7 = C/(2(pi)) + 7
3) O, the outer circumference = (pi)*(2R) = {{{(pi)*(2*( C/(2(pi)) + 7 ))}}}
or {{{(pi)*(2*( 220/(2(pi)) + 7 ))}}}, where 220 is the inner circumference.
4) Multiply by 2 to give us the number of rupees
{{{2*((pi)*(2*( 220/(2(pi)) + 7 )))}}}=
{{{4*(pi)*( 220/(2(pi)) + 7 )}}}=
{{{( (4*(pi))*(220/(2(pi))) + 7*(4*(pi)   ) )}}}=
{{{( (2)*(220) + 7*(4*(pi)   ) )}}}=
{{{ 440 + 28*(pi) }}}, the number of rupees