You can put this solution on YOUR website!
Let x = the number of widgets that John sold
Let 2.5x= the number of widgets Harvey sold (2.5 times as many as John)
the difference indicates a subtraction problem:
Combine like terms:
Divide both sides by 1.5:
John sold 58 units, Harvey sold 145 units (2.5*58)
145-58=87 so this is correct.