350 hamburgers were sold on the Sunday.
Step-by-step explanation
Suppose, the number of hamburgers sold on the Sunday was
![x](https://img.qammunity.org/2019/formulas/mathematics/college/lhtxftojjkzsmo3o2h4ilq8naohracejui.png)
As there were 67 more cheeseburgers sold than hamburgers, so the number of cheeseburgers sold
![=x+67](https://img.qammunity.org/2019/formulas/mathematics/high-school/qffov5rrd5gqn9cig5wycr9bhwxs5t0q7l.png)
Given that, the total number of hamburgers and cheeseburgers sold was 767. So, the equation will be.....
![x+(x+67)= 767\\ \\ 2x= 767-67\\ \\ 2x=700\\ \\ x= (700)/(2)=350](https://img.qammunity.org/2019/formulas/mathematics/high-school/jddwkkilnutnmkpnj6vdhp7ledetg0vjet.png)
So, the numbers of hamburgers sold on Sunday was 350.