EMS Courier — Custom Duty Charges can't be so higher 41.??%

Address:

Mumbai City, Maharashtra, 400053

I have ordered Bluboo Dual a smartphone from china worth Rs.7, 578.59/-. It arrived at EMS Mumbai branch, as I have given an address of mumbai. When I went there to clear the same as a customer, they have demanded the custom duty of 41.??% and i was so shocked that how can they charge so?

Where product is only of 7k and they are asking to pay the duty almost 50%.
As I have ordered for the first time, i dont know the rule of custom and its very difficult to find the rules online.

Please help me with the same.

Is it actually 41% or EMS people are playing with me as i have not collected the mobile yet from EMS Custom Office, Mumbai.