Q. Activity A is worth $200, is 100% complete and actually cost $200. Activity B is worth $75, is 90% complete, and actually cost $120 so far. Activity C is worth $200, is 75% complete, and has cost $175 so far. The total budget is $1000. What is the schedule variantce of the activities listed?

A. -$77.50
B. -$57.50
C. 0.84
D. 0.88

The answer given is B. How do we arrive at the calculation? I tried the below calculation