Dear Varun,
What the " Act " you referred to is the Minimum Wages Act,1948 which alone fixes the quantum of wages payable to industrial employees that too selectively as a first step towards the realization of the ideal of securing " Living Wage " to the working class as per Article 43 of the Constitution of India. Though the terms ' wage', 'salary' and 'remuneration' have similarities in their colloquial meanings in terms of nature and outflow, they have certain subtle dissimilarities or differences in their literary and legal definitions in terms of the periodicity of payment, method of computation, the nature of services in consideration of which the payment is made and the addition of certain components resulting in a structural pattern. Apart from the MW Act,1948 is the only Act fixing the minimum rate of wages payable in respect of certain scheduled employments like I said earlier, there are other legislations relating to wages exclusively too viz., the Payment of Wages Act,1936 dealing with the mode and periodicity of payment of wages and the legal deductions therefrom and the Equal Remuneration Act,1976 mandating equal wages for equal work irrespective of sex and some other legislations like the Industrial Disputes Act,1947, the ESI Act,1948, the EPF Act,1952, the Payment of Bonus Act,1965, the Payment of Gratuity Act,1972 having their own modified definitions of wages depending upon their respective purposes. Therefore, when you intend to break the gross or total wages of a given wage period e.g., monthly wages in to different components such as basic and allowances, you have to ensure compliance with all these Labor Laws which have different definitions of the same term.
Basic and Dearness Allowance being the major components invariably finding place for consideration in almost all the Legislations mentioned above, you may consider the break up of Basic and D.A together 70%+ Other Allowances 30%. Such a practice would ensure unquestionable compliance with all enactments and avert the heart burns of employees regarding their indirect/fringe benefits.
Any way, do not start the calculation with CTC.