At an annual interest rate of i, i 0, the present value of a perpetuity paying 10 at the end of each three-year period, with the first payment at the end of year 3, is 34.21. At the same annual effective rate of i, the present value of a perpetuity paying 1 at the end of each four-month period, with the first payment at the end of four months, is X.

Calculate X.