Question
What is the age of a class teacher? I. There are
13 students in the class. II. The average age of students and the teacher is 16 years. III. The average age of the teacher and the students is 4 years more than that of the students. In each of the following questions, a question is followed by information given in three statements. You have to study the question along with the statements and decide that the information given in which of the statements is necessary to answer the question.Solution
By combining all the three statements, Average age of student and teacher = 16 × 14 = 224 years. Average age of 13 students = 16 – 4 = 12 years. Total age of 13 students = 13 × 12 = 156 years. ∴ Teacher’s age = 224 – 156 = 68 years.
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