Consider two following two perpetuities.

A perpetuity-immediate with effective interest rate of i. The payment is constant and equal to 100 in the first 2n years. Starting from time 2n + 1 and for all future years, the payment increases by K% each year, i.e. payment is 10(1 + K%) for year 2n + 1, then 10(1 + K%)^2 and so on. The present value is $3,600.

At the same interest rate i, the present value of a 2n-year deferred increasing perpetuity-immediate, with first payment equal to 20(1 + K%) and then increasing by K% each year, is equal to $3,800.

Known that the quantity v^n = (1 + i)^(n) = 0.7, calculate K%