That is, the number of students who answered the questionnaire was 48;
(2)48×25%= 12 (person)
That is, the number of people who like the second method is 12.
Complete the statistical chart as follows:
.
(3) The proportion of people who like ① = 1648= 13,
Like the proportion of ② = 14,
The proportion of people you like ③ = 14,
Like the proportion of ④ =848= 16,
Then the favorite teaching method of the whole grade students is the fourth one.
The number of people who choose this method =420× 13= 120.
The fan-shaped central angle of people who like this method = 360× 13 = 120.