The probability of failing an examination is 0.25. a) What is the probability of passing the examination? b) If 900 students sat for the examination, how many of them passed the examination?

Here's how to solve this probability problem: a) What is the probability of passing the examination? Step 1: Understand that the probability of an event happening and the probability of it not happening sum to 1. P(passing) + P(failing) = 1 Step 2: Substitute the given probability of failing and solve for the probability of passing. P(passing) + 0.25 = 1 P(passing) = 1 - 0.25 P(passing) = 0.75 The probability of passing the examination is 0.75. b) If 900 students sat for the examination, how many of them passed the examination? Step 1: Use the probability of passing found in part (a) and the total number of students. Number of students who passed = Total number of students × Probability of passing Step 2: Calculate the number of students who passed. Number of students who passed = 900 × 0.75 Number of students who passed = 675 The number of students who passed the examination is 675. That's 2 down. 3 left today — send the next one.