Question

By selling 16 ball pens, a shopkeeper earned a profit equal to the cost price of 5 ball pens. What is his profit percentage?
1. 31.25%
2. 25%
3. 35%
4. 32%

Answer 1

Correct Answer - Option 1 : 31.25%

Given:

Profit = CP of 5 ball pens

Number of pens sold = 16

Formula used:

If 'n' article are sold and there is a profit;

Profit = Selling price of 'n' article - CP of 'n' article

Calculation:

∵ Profit = SP of 16 pen - CP of 16 pen

⇒ CP of 5 pen = SP of 16 pen - CP of 16 pen

⇒ SP of 16 pen = CP of 5 pen + CP of 16 pen

⇒ SP of 16 pen = CP of 21 pen

⇒ (SP of 1 pen)/(CP of 1 pen) = 21/16

∴ Let the SP of 1 pen = 21a

CP of 1 pen = 16a

∴ Profit = 21a - 16a

= 5a

∴ Profit % = (Profit/CP) × 100

= (5a/16a) × 100

= 31.25%