# Calculate Selling Price using Cost and Profit Percent

How to calculate selling price using cost and profit percent?

We know, selling price = cost price + profit

selling price = cost price + profit%/100 × cost price

selling price = 100 × cost price + profit% × cost price/100

selling price = (100 + profit%)cost price/100; [Here, cost price and profit% are known.]

1. Ryan bought a book for $100 and sold it at a profit of 10%. Find the selling price of the book. Solution: Given cost price of the book =$100

Profit% = 10%

We know, selling price = (100 + profit%)cost price/100

= (100 + 10)100/100

= (110)100/100

= 110 × 100/100

= $110 Therefore, the selling price of the book is$110.

2. John bought a music system for $260. For how much should he sell the music system to gain 10%? Solution: Given cost price of the music system =$260

Gain% = 10%

We know, selling price = (100 + gain%)cost price/100

= (100 + 10)260/100

= (110)260/100

= 110 × 260/100

= $286 Therefore, he should sell the music system for$286.

3. Robert bought a machine for $1200 and sold it at a profit of 15%. Find the selling price of the machine. Solution: Given cost price of the machine =$1200

Profit% = 15%

We know, selling price = (100 + profit%)cost price/100

= (100 + 15)1200/100

= (115)1200/100

= 115 × 1200/100

= $1380 Therefore, the selling price of the machine is$1380.

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