Question

By selling a book for ₹150, a person gains 20% . At what price should he sell it so as to gain 25%.

Answer 1

SP of the book is ₹ 150

Gain % = 20%

Gain % = Gain/CP × 100%

CP = SP - Gain

CP = ₹ 150 - Gain

==> Gain % = Gain / ( ₹150 - Gain )× 100%

==> 20% = Gain /( ₹ 150 - Gain ) × 100 %

==> Gain / ( ₹ `150 - Gain ) = 1 / 5

==> 5 Gain = ₹ 150 - Gain

==> 6 Gain = ₹ 150

==> Gain = ₹ 150 / 6

==> Gain = ₹ 25

CP = ₹150 - ₹25

     = ₹125

For Gain to be 25%

25% = Gain/C.P×100%

==> Gain / CP = 1/4

==> Gain /₹125 = 1/4

==> Gain = ₹125/4

==> Gain = ₹31.25

SP = CP + Gain

     = ₹125 + 31.25

     = 156.25

The selling price should be ₹ 156.25

Hope I helped u

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