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Haidian Yimei Mathematics Answer 20 17
(1) Select two students whose math scores are lower than 120. The basic events of all possible results are: {A, B}, {A, C}, {A, D}, {B, C}, {B, D}, {C, d} * * 6. ...

Since everyone has an equal chance of being elected, the possibility of these basic events is also equal.

The math scores of the two selected people are below 1( 10): {A, B}, {A, D}, {B, d} * * 3...4.

Therefore, the probability that the math scores of the selected two people are below 1 10 is p = 36 = 12...5.

(2) Choose two students from this group, and the basic events of all possible outcomes are: {A, B}, {A, C}, {A, D}, {A, E}, {B, C}, {B, D}, {B, E}, {C, D}.

Since everyone has an equal chance of being elected, the possibility of these basic events is also equal.

The two selected people scored above 90 in math and [86, 1 10] in Chinese. There are three events: {A, D}, {A, E}, {D, e} * *. … 12

Therefore, the probability that the selected two students scored above 90 in mathematics and [86, 1 10] in Chinese is P=3 10… 13.