Three successive discounts of 25% each on the marked price of an item are together equivalent to a single discount (correct up to 2 decimal places) of:

Three successive discounts of 25%.

Discount =$$\text{ Marked Price} \times \frac{ 100 - Discount}{100}$$​​

Let the Marked Price be 100.

then, $$100 \times \frac{75}{100}\times \frac{75}{100}\times \frac {75}{100} = 42.18$$  

Discount,

 100 - 42.18 = 57.82 %  $$\approx$$ 57.81 % 

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