Step-by-step explanation: 20 mins = 10 jumps now 20x3 is 60 which is an hour so in an hour he would have jumped 30 times and if you times 30 with 9 you would get 270 hence your answer
to find how much shoes he would have to sell take away 40 from both sides of the equation which would leave you with 4.50x=72 next divide 4.50 out of both sides of the equation x=16 so he would have to sell 16 pairs of shoes a day to meet his goal
