**Probability**

# Question 1:

**Exercise 15A**

# Question 2:

**Question 3:**

**Question 4:**

**Question 5:**

**Question 6:**

Number of tests in which he gets more than 60% marks =2 Total numbers of tests =6

∴ Required probability

# Question 7:

**Question 8:**

**Question 9:**

**Question 10:**

Total numbers of students =30

Numbers of students who lie in the interval21-30=6

∴ Required probability