20 teachers of a school either teach Mathematics or physics. 12 of them teach Mathematics while 4 teach both the subjects. Then, the number of teachers teaching Physics only is

20 teachers of a school either teach Mathematics or physics.�

1.	20 teachers of a school either teach Mathematics or physics. 12 of them teach Mathematics while 4 teach both the subjects. Then, the number of teachers teaching Physics only is
A.	12
B.	8
C.	16
D.	None of these
Answer» B. 8

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