Anna's current number of points = 225 points.
She danced correctly and earned = 75 points.
And when she danced incorrectly she loses = 30 points.
Note: For dancing correctly earned points will be added and for dancing incorrectly loses points will be subtracted from the total points has in starting.
So, we can setup an expression as
Current points + earned points - loses points
Plugging values, we get
225 +75 -30 Required expression.
Adding 225 and 75, we get 300.
Therefore, 225 +75 -30 = 300-30.
Subtracting 30 from 300, we get
300-30=270.
Therefore, Anna's final score is 270 points.
