The selling price of an article marked for ₹10000 after giving three discounts, 20%, 10% and k% is ₹6120. What will be selling price (in ₹) of the same article if a single discount of (k+20)% is allowed?

6500

Three discounts, 20%, 10% and k% 

SP = ₹6120

MP = ₹10000

ATQ,

10000 × \(\frac{4}{5}\) × \(\frac{9}{10}\) × k% = 6120

k% = 6120 × \(\frac{5}{4}\) × \(\frac{10}{9}\) × \(\frac{1}{10000}\) = 0.85% or 85% or the discount is 15%

If the discount is k + 20% = 15% + 20% = 35%

Then the selling price is = 10000 × \(\frac{(100 - 35)%}{100}\) = 6500