Twelfth grade examination results. The Central Board of Secondary Education (CBSE) is a national level board of education in India for public and private schools, controlled and managed by the Government of India. CBSE reports that there is an improvement in the overall twelfth grade (class 12) examination results in 2020 compared to 2019. The 2020 results show that 88.78% of students passed the exams and about 15% of students scored 90% or above. Consider a random sample of exam results from 10 twelfth grade students in 2020.

a. What is the probability that more than half have passed the exams?

b. What is the probability that more than half those who passed the exams scored 90% or above?