84
Step-by-step explanation:
Pretend her first 3 quizzes were all 83 since that was the average. So the 4th was 87.
83+83+83+87 = 336
Divide by the total number of quizzes because they are equally weighted.
336/4 = 84
Her new average score is 84.
28t-140y
step by step explanation: