Among 180 students in a room, 70 study mathematics, 100 study science, and 100 study computer programming.

Among 180 students in a room, 70 study mathematics, 100 study science, and 100 study computer programming. Also, 30 students study mathematics and science, 40 students study mathematics and computer programming, and 50 students study science and computer programming. We know that 10 students study all three subjects. How many of these students study none of the three subjects?

10

15

20

35