Question

a tricycle is sold at a gain of 15%. Had it been sold for ₹108 more the profit would have been 20% find the cost price

Answer 1

method 1
let the CP be Rs x
now, gain % =15%
gain = 15x/100 =3x/20
so, SP =CP + gain
            = x+ 3x/20
            = 23x/20
now, if SP = 23x/20 + 108
gain % = 20
gain = 20x/100 = x/5
SP = x+x/5 = 6x/5
but SP =23x/20 + 108
so,
23x/20 + 108 = 6x/5
⇒6x/5 - 23x/20 = 108
⇒x/20 = 108
⇒x = 2160
so, CP = Rs 2160

method 2
20% - 15% = 108
5% =108
1% = 108/5
100% = (108/5)×100
          =Rs 2160