Explanation:
First of all, let us lay down the clues;
●There is a 20% discount on the mobile set.
●The price after the discount is Rs 13 920
●We need to find the original price.ie.(100% stands for original price)
Now let's start;As there is a 20% Discount on the m.Set, we need to find the exact percentage decrease.
So,
100%-20%= 80%
Now let's do Direct Proportion,
80%= Rs 13 920
1%= 13 920/80
100%= 13 920/80*100=Rs 17 400
Your FINAL ANSWER;
RS 17 400