So now as per your information sale price in F.Y. i.e. Financial year 2017-18 comes to RS. 1835000 and so now the indexed cost of acquisition comes to RS. 326400 based on your fair market value for F.Y. 2000-01 (120000/100*272)
So capital gain =[deleted] = 1508600.
Now let's talk about tax on such capital gain, if doesn't matter if you are government employee and your brother is not and if you are in 30% tax slab your brother is not.
Long term capital gain rate is 20% of capital gain for everyone.
So capital gain for you and your brother would be 1508600/2*20%= 150860
Because of such high tax you will also have to pay interest of not paying advance tax on such gain.
You can save such capital gain tax by either investing your share of amount in residential property u/s 54 or by investing the amount for 5 years in specified bonds mentioned by government u/s 54EC.
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