Answer:
![X \sim Unif (a= 0, b=60)](https://img.qammunity.org/2021/formulas/mathematics/college/1p7o97aboyffv2z8ku9rqg5lp45bxb39ci.png)
And we want to find the following probability:
![P(X>30)](https://img.qammunity.org/2021/formulas/mathematics/college/v0km51auk6rfeonuohd6vk0nqh6rgul0bc.png)
And for this case we can use the cumulative distribution given by:
![F(x) =(x-a)/(b-a), a \leq x \leq b](https://img.qammunity.org/2021/formulas/mathematics/college/67eupcfsxddddt36zhph8859htp196q2wi.png)
And for this case if we use this formula and the complement rule we have:
![P(X>30)= 1-P(X<30) = 1- (30-0)/(60-0)= 1-0.50= 0.50](https://img.qammunity.org/2021/formulas/mathematics/college/8ecvv3e559uh5xb6pnscjjmchjouhfjvon.png)
Explanation:
Let X the random variable who represent the pizza delivery time and we know that the distribution for x is given by:
![X \sim Unif (a= 0, b=60)](https://img.qammunity.org/2021/formulas/mathematics/college/1p7o97aboyffv2z8ku9rqg5lp45bxb39ci.png)
And we want to find the following probability:
![P(X>30)](https://img.qammunity.org/2021/formulas/mathematics/college/v0km51auk6rfeonuohd6vk0nqh6rgul0bc.png)
And for this case we can use the cumulative distribution given by:
![F(x) =(x-a)/(b-a), a \leq x \leq b](https://img.qammunity.org/2021/formulas/mathematics/college/67eupcfsxddddt36zhph8859htp196q2wi.png)
And for this case if we use this formula and the complement rule we have:
![P(X>30)= 1-P(X<30) = 1- (30-0)/(60-0)= 1-0.50= 0.50](https://img.qammunity.org/2021/formulas/mathematics/college/8ecvv3e559uh5xb6pnscjjmchjouhfjvon.png)