A math contest * * * has 50 participants and 20 students won prizes. Their average score is 4 points higher than the winning score. The average score of 30 students who didn't win the prize was lower than the winning score 1 1 point. The average score of all students is 87. What's the winning score?

The total score is:

50×87=4350 (minimum)

The total score of the winning students is higher than the total score:

4×20=80 (minimum)

The total score of students who didn't win the prize is lower than the total score:

30× 1 1=330 (minutes)

The winning score is:

(4350-80+330)÷50=92 (points).

A: The winning score is 92 points.