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Science Mathematics 18 in Jiangxi College Entrance Examination in 2009
Regard this issue as an independent and repetitive event,

The probability that each college student will receive 6.5438+10,000 yuan of financial aid is P 654.38+ 0 = 654.38+0/4.

The probability of each college student getting 50,000 yuan is P2 = C (1, 2) * (1/2) * (1/2) =1/2.

The probability of each college student getting a grant of 0,000 yuan is P3= 1/4.

The values of 1)ξ are 0,5, 10,15,20,25,30.

When ξ=0, all three are funded, P = C (0 0,3) * (1/4) * (1/4) =1/64.

When ξ=5, one in three people gets 50,000 yuan.

P=C( 1,3)*( 1/2)*( 1/4)*( 1/4)= 3/32

When ξ= 10, one of the three people got a subsidy of 654.38+10,000 yuan, or two people returned 50,000 yuan.

P=C( 1,3)*( 1/4)*( 1/4)*( 1/4)+C(2,3)*( 1/2)*( 1/2)*( 1/4)

= 15/64

When ξ= 15, one of the three people will receive a subsidy of 6,543,800 yuan, the other will receive a subsidy of 50,000 yuan, or all three will receive a subsidy of 50,000 yuan.

p =( 1/2)*( 1/2)*( 1/2)+C( 1,3)*( 1/4)*C( 1,2)*( 1/2)*( 1/4)

=5/ 16

When ξ=20, two of the three people will get 6.5438+million yuan, or one person will get 6.5438+million yuan, and the other two will get 50,000 yuan.

P=C(2,3)*( 1/4)*( 1/4)*( 1/4)+C( 1,3)*( 1/4)*( 1/2)*( 1/2)

= 15/64

ξ=25: 00, two of the three people receive 6.5438+10,000 yuan, and the other receives 50,000 yuan.

P=C(2,3)*( 1/4)*( 1/4)*( 1/2)= 3/32

When ξ=30, all three people will get 654.38+ ten thousand yuan.

p =( 1/4)*( 1/4)*( 1/4)= 1/64

2) Expected to be equal to 15.