Praxis 5511 Practice Test Practice Question
In a classroom survey of 28 students, 20 students have at least 1 sibling and 17 students have at least 1 cousin. Of these students, 12 have at least 1 sibling and at least 1 cousin. How many of the students surveyed have no siblings and no cousins?
Correct Answer: C
Rationale: To find the number of students with no siblings and no cousins, we can use the principle of inclusion-exclusion. Start with the total number of students, which is 28.
From the survey, 20 students have at least one sibling, and 17 have at least one cousin. Among these, 12 students have both siblings and cousins.
Using the formula:
Total with siblings or cousins = (students with siblings) + (students with cousins) - (students with both)
= 20 + 17 - 12 = 25.
Thus, the number of students with neither siblings nor cousins is:
28 - 25 = 3.
Option A (1), B (2), and D (4) do not match this calculation, confirming that C is the only valid choice.
Unlock All Questions
Subscribe to Premium for full access to all practice questions, detailed rationales, and performance tracking.
Subscribe Now