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20 13 Hunan mathematics liberal arts
(1) According to statistics, m = 60.006 = 1000,

m= 1000-6-82-256-220=436,

n=436 1000=0.436,N=220 1000=0.220。

The histogram of frequency distribution is shown in the following figure:

(2) Let the number of people with 90 points or above in liberal arts mathematics in the city be X,

Then 100020000 = 656x, and x =13120;

(iii) Let four boys be represented as A 1, A2, A3, A4,

Three girls are represented as B 1 of B3 B2,

The basic events of recruiting 2 students from 7 students are:

(A 1,A2),(A 1,A3),(A 1,A4),(A 1,B 1),(A 1,B2),(A 1,B3)、

(A2,A3),(A2,A4),(A2,B 1),(A2,B2),(A2,B3),(A3,A4),

(A3,B 1),(A3,B2),(A3,B3),(A4,B 1),(A4,B2),(A4,B3),

(B 1, B2), (B 1, B3), (B2, B3), ***2 1 species.

We take "there are 1 girls in 2 people" as event A, and there are:

(A 1,B 1),(A 1,B2),(A 1,B3),(A2,B 1),(A2,B2),(A2,B3)、

(A3,B 1),(A3,B2),(A3,B3),(A4,B 1),(A4,B2),(A4,B3),

*** 12 species,

∴P(A)= 122 1=47.

So two out of seven people are admitted, and the probability that 1 happens to be a girl is 47.