As the price of mango has reduced 20%, it is now possible to buy 2 more mangoes at Tk. 12. What is the correct price of 50 mangoes?

As the price of mango has reduced 20% that means
mango of Tk. 100 will be available for Tk. 80
Therefore, mango of Tk. 12 will be available for Tk. (80 × 12/100) or Tk. 9.6
So, cost price of 2 mangoes = (12 - 9.6) = Tk. 2.4
cost price of 50 mangoes = Tk. 2.4 × 50/2 = Tk. 60
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short-cut
20% of Tk. 12 = Tk. 2.4
The price of 2 mangoes is Tk. 2.4
The price of 50 mangoes is Tk. 2.4 × 50/2 = Tk. 60