Answer:
![x=1(3)/(4)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/38dz0f1o1xrpphis3yu8zb9j5pqr6kh039.png)
Explanation:
We are given that a recipe required flour=
![5(1)/(2)=(11)/(2)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/mn0dwnarj26wfozcw4c8187myxen8x2o2s.png)
Lorenzo has flour=
![3(3)/(4)=(15)/(4)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/i8i87nl8evn4n2z9m2hc3b8v45uf10a0xz.png)
We have to find an equation to find the additional amount of flour Lorenzo needs to make the recipe.
Let x be the additional amount of flour that is required to make the recipe
According to question
![x+(15)/(4)=(11)/(2)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/auutp9otc9rhbuoivm9dhr4q7vpoi5uiu1.png)
![x=(11)/(2)-(15)/(4)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/isi1zdcph2icpyot7sol6fnyafbps7z8kj.png)
Using subtraction property of equality
![x=(22-15)/(4)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/p4008qkwlg9cknj1o3q9fvm1roqyqxbfvv.png)
![x=(7)/(4)=1(3)/(4)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/6c9zd06940fwyrap9ecb3oauxkco06kg9n.png)
Hence, Lorenzo needs additional amount of flour to make recipe=
![1(3)/(4)](https://img.qammunity.org/2019/formulas/mathematics/college/1seeo88e1kfrgrsjma9su3zkxv6oa8qik5.png)