The NUMBER of students who like science but not math is 180.

Step-by-step explanation:

We are GIVEN that there are 500 students in a school 220 like science subject 180 like math and 40 like both math and science.

Let the number of students who like science subject = N(S) = 220

Number of students who like math subject = n(M) = 180

Number of students who like both math and science subject = n() = 40

Now, it is given that the number of students who like science subject is 220 but among these students there must be some students who like math also.

And the number of students who like both math and science is 40.

This means that if we subtract those students who like both science and math from the given number of students who like science subject, then we will get those students who like science but not math.

SO, number of students who like science but not math = n(S) - n()

                                                                                               = 220 - 40

                                                                                               = 180 students.