Tomas bought 3 software apps and 2 e-books for a total of $21. The two e-books cost $12. If s represents the cost of each app, the total cost of all 5 items is represented by mc021-1.jpg. Which statement about verifying the solution for s is true?
First compute the cost of the three apps: [tex]21-12=9[/tex] The cost of the three apps is $9 then. Since s is the price of the apps, we deduce the equation: [tex]3s=9[/tex] which means that [tex]s=3[/tex]