maximum marginal rate

MMR is 30+15+3% = 35.535%

Sir,
Now that 3% replaces with 4% for the A.Y 2019-20

then it will be  30+15+4% = 35.88% 

Section 2(29C) of the Income Tax Act, 1961 defines "Maximum Marginal Rate" to mean the rate of income tax (including surcharge on income-tax, if any) applicable in relation to the highest slab of income in the case of an individual, AOP or BOI, as the case may be, as specified in the Finance Act of the relevant previous year.