Leah either can buy the tablet or the mp3 player.
Darnel is able to buy only the mp3 player.
1) If the sales tax is 9% then the cost will be increased by 9% for the customers (Leah and Darnell)
2) Note that there is a discount for the tablets (20%) and mp3 players (25%)
So, we can write out the following for the tablet
![\begin{gathered} 300*(1-0.2)*(1+0.09)= \\ 240*(1.09)=\$261.60 \\ mp3\:player: \\ 120*(1-0.2)*(1+0.09) \\ 96*(1.09)=\operatorname{\$}114.06 \end{gathered}]()
3) As we can see since Leah has saved $350, She cannot buy both, she either can buy the tablet or the mp3 player.
Darnel is able to buy only the mp3 player with the money he's saved.