Question

rahul bought pens at 120 a dozen he sold it foe15 each.wha is his profit per cent

Answer 1

1 dozen =120 rs
1 pen = 120/12
1 pen cost = 10 rs
selling price = 15 rs
profit = 15 - 10 = 5 rs for each pen
profit % = profit / CP × 100
= 5/ 10 × 100
= 50%

Answer 2

Rahul bought 120 rupees of pens of dozen

1 dozen = 12 items

rate of 1 pen is 120÷12=10 rupees

but, Rahul sold for 15 rupees each.

means 5 rupees gain for 1 pen

for a dozen pens = 5*12 = 60 rupees gained

P% = profit/C.P*100

= 60/120*100%

= 1/2*100%

= 100/2%

= 50%

hence,. the profit per cent is 50..