It seems the charges are high!
Your job is comparatively small.Hence overhead charges are generally more. But that doesn't mean the costing will go up this much high, as per my experience.
Simply calculate as follows,
Marble cost say, 55.00
Sand and cement, white and grey with color etc. (max.) 5.00
Labour charges (In big jobs it is (Rs.15/sft),say 20.00
Supervision charges (5% max) 4.50
Tax (If he pays?) (15%...max) 15.00
Profit, (say 20% max., note: supervision charges separate) 22.00
Thus total with considering all max factors it will reach to Rs. 132.00
In short I suggest you to take minimum 3 no. quotations from genuine contractors, discuss and negotiate. Do small calculations of 7th standard. and reach to a conclusion. I will not say contractor is wrong! His credibility, quality of supervision, experience and time guarantee of finish of work and rectification alertness also matters. You have to consider all factors before judging the contractor. Really skilled and experienced Mason is the asset of the contractor. You see from how many years he is working with that contractor. Also see at least two works done by him (contractor and tiler, before doing job).
My calculations are just guidelines to you for taking final decision. This is general practice in MUMBAI. The tax payer contractors charge more.
Anyway thanks and best luck.