Question

John paid $330 for a new mountain bike to sell in his shop. He wants to price it so that he can offer a 10% discount and still make 20% of the price he paid for it. At what price should the bike be marked?

I do not understand the explanation already posted, to this problem. Please give further explanation how the doemula was created? .9%? where dis that come from?

Answer 1

John wants to make a profit 20% means we can say that,

selling price = 120% of cost price

He wants to offer 10% of discount such that he can still make a profit of 20% means he has to sell a mountains bike such that after giving a 10% discount he must get $396

we know that after selling a item with 10% discount we can write,

Here 90% comes because john is giving 10% discount hence 100% - 10% = 90%

we have a selling price = $396 hence,

Hence we can say that john should marked a bike for $440 so that he can give a discount of 10% and make a profit of 20%

Or simply,

x - 10%x = 396

x - 0.1x = 396

x(1-0.1) = 396

0.9x = 396

x = 440