Question

Venn diagram
Out of a group of 20 teachers in a school 10 teach maths, 9 teach physics and 7 teach chemistry. 4 teach maths and physics but none teach both maths and chemistry. How many teach both chemistry and physics and how many teach only physics

Answer 1

Answer:

In one group teachers in a school=20

and 10 teach maths

and 9 teach physics

and 7 teach chemistry

and there are teach math and physics =4