Answer:
64%
Step-by-step explanation:
The real value of the land is calculated as;
Real value = nominal value / CPI x 100
now as CPI of 1970 is 100. Then, 1970 is the base year.
The real value is equal to nominal value in the base year.
The nominal gain in capital is
100,000 - 10,000 = 90,000
Tax rate on gain 20%
20% of 90,000
= 18,000
After tax nominal value of capital
100,000 - 18,000 = 82,000
Real value of after tax capital
82,000 / 500 x 100 = 16,400
Gain in real after tax capital is
Gain =16,400 - 10,000 / 10,000 x 100
= 64%