Fixed Budget is mainly based on assumptions which are unrealistic and so this is not applicable to business concerns, but if we talk about Flexible Budget, it is more practicable. The former is does not help to make a comparison if the actual and budgeted outputs differ, but the latter proves to helpful to judge the performance by comparing actual output with the budgeted targets. Cost Ascertainment is also not possible in case of fixed budget if the actual and budgeted levels of activity vary and the same can be easily determined in the case of a flexible budget.
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