In a class the average age of 20 students and a teacher is 20 years. What is the age of the teacher ?
I The teacher's age is 20 years more than the age of the eldest student.
II The average age of the 20 students without the teacher is 18 years.

A. If the question can be answered by using statement (I) alone but cant be answered by using statement (II) alone.

B. If the question can be answered by using statement (II) alone but cant be answered by using statement (I) alone.

C. If both statements (I) and (II) are required to answer the question.

D. If the answer can be obtained by using either of the two statements alone.

Answer & Explanation

Answer : Option
B

Explanation :

Statement (II) alone is sufficient but statement (I) alone is not sufficient.

Total age including teacher is 21 x 20 = 420

Total age of students without teacher = 20 x 18 = 360