well seeing that he already gets 300 he only needs to make 200 so do 200 divided by 15 which would equal 13.33 repeating so if he sold 14 bikes he would have $210 300 + 15(b)=500 1st step 500-300=200 2nd step 200/15=13.33 round to 14 step 3 14x15=210 so he would need to sell 14 bikes
