Answer:
Correct option is (C)
Explanation:
we are given that -Tim design a pair of shorts,S, and T-shirts,t.
Tim sell Sorts for $12 and T-shirts for $8 each.
Tim can work atmost 18 hours a day so we can write
![time\leq 18](https://img.qammunity.org/2020/formulas/mathematics/middle-school/e1riu8dx3agtw8vcvuvi529lww0trgc4cq.png)
Time taken to design a T-shirt is 30 minutes and for Shorts, it is 45 minutes.
![(30)/(60)t+(45)/(60)s\leq 18\\\text{Multiply both the sides by 60}\\30t+45s\leq 1080\\\text{Divide both the sides by 45}\\s+0.66t\leq 24\\\text{Subtract 0.66t from both the sides}\\s\leq 24-0.66t](https://img.qammunity.org/2020/formulas/mathematics/middle-school/mgybjcp2u9y7w41zkj996upou2cwr1jdt7.png)
He must design 12 itesm each day, so we can write
![t+s\geq 12](https://img.qammunity.org/2020/formulas/mathematics/middle-school/hwkpy318836xsqeqeicg45jrtk0ai70kmz.png)
Further it can be written as
![t+s\geq 12\\\text{Subtract t from both the sides}\\s\geq 12-t](https://img.qammunity.org/2020/formulas/mathematics/middle-school/8gwv0oc4lu3rjzd80v5xoucp3lyqs80o3k.png)
Also Tim can not design more than 30 items in one day, so we can write
![t+s\leq 30\\\text{Subtsract t from both the sides}\\s\leq 30-t](https://img.qammunity.org/2020/formulas/mathematics/middle-school/3udxj5btr435srz2fn1fg0prl18h700gq9.png)
Hence from the above equations , its claer that
![s\geq 12-t,s\leq 30-t,s\leq 24-0.66t,s\geq 0,t\geq 0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/kh7noww7ym3rbg0sowzttk7d9k25s6l9k3.png)