Question

A shopkeeper bought 121 pencils for 10 and sold at 10 for 11 find his gain or loss persent?

Answer 1

CP : 11 pencil = $10S P : 10 pencil = 11multiply CP by 10 and SP by 11   . now you get two equation.C P : 110 pencil = 100S P : 110 pencil = 121profit = 121 - 100 = 21profit percentage = (21÷100) × 100 = 21% percent

Answer 2

C.P of 121 pencils = 10
C.P of 1 pencil = 10/121
S.P of 10 pencils = 11
S.P of 1 pencil = 11/10
Gain = S.P - C.P
= 11/10 - 10/121
= 1231/1210
Gain % = (Gain/C.P) × 100
= {(1231/1210)/(10/121) × 100
= 21%