Help me answer simply im p6 and didnt learn algebra yet

$$40 - 28 = 12$$

There were 12 students in the Yellow Group.
The student's work for part (a) is ✅ Correct.

$$1040 - 674 = 366$$

The students in the Yellow Group collected \boxed{366}$. The student made a small arithmetic error in their subtraction ($1040-650$instead of$1040-674$).

$$\frac{366}{12} = 30.50$$

The average amount collected by each student in the Yellow Group was \boxed{30.50}$. The student used an incorrect total for the Yellow Group's collection and divided by the total number of students (40) instead of the number of students in the Yellow Group (12).