Dear Vineet,
As per the Income Tax Act, while calculating the capital gain on foreign investment in shares, impact of foreign currency fluctuations should be considered in it. Meaning thereby in your case, Capital Gain Tax will be calculated as follows:
Sales Consideration: 150*75= 11,250
Cost of Acquisition (COA): 100*70= 7000
Short Term Capital Gain= Rs. 4,250
* It will be considered as short term capital gain as shares were sold with is a period of 3 months which are less than the period ( i.e 24 months)required to qualify as long term capital gain.
Tax Rate on Short Term Capital Gain is 30% i.e (Rs. 4250*30%= Rs.1,275)
Also, as per the Tax Avoidance Treaty between US and India, tax is paid in US on this capital gain can be claimed as credit in India while filing the Income Tax Return.
Thanks and Regards
Divya Chugh