Answer:
The number of tickets they need to sell is
![n=(p)/((d-c))](https://img.qammunity.org/2021/formulas/mathematics/high-school/d5ilbnnuoq341928vvc5lcw246uv6u4llt.png)
Explanation:
The formula is p = n(d - c), where
- P is the total profit made from the event
- n is the number tickets sold
- d is the price charged for each dinner
- c is the cost of food per plate
To find the number of tickets they need to sell separate n in one side and the other variables p, d and c in the other side
p = n(d - c)
n is multiplied by the difference of d and c, so lets divide both sides by the difference of d and c
![(p)/((d-c))=(n(d-c))/((d-c))](https://img.qammunity.org/2021/formulas/mathematics/high-school/j23perja3y1ntymcds70g2avk1vtdk060k.png)
Cancel (D_C) up with (d - c) down in the right hand side
![(p)/((d-c))=n](https://img.qammunity.org/2021/formulas/mathematics/high-school/9n9v9syipwrbxx1b55xgkipku83lklvkrz.png)
Switch the two side
![n=(p)/((d-c))](https://img.qammunity.org/2021/formulas/mathematics/high-school/d5ilbnnuoq341928vvc5lcw246uv6u4llt.png)
The number of tickets they need to sell is
![n=(p)/((d-c))](https://img.qammunity.org/2021/formulas/mathematics/high-school/d5ilbnnuoq341928vvc5lcw246uv6u4llt.png)