Let ξ 1, ξ2, ... are independent sequences of random variables, and each sequence has its own mathematical expectation e ξ 1, e ξ 2, ... and its variance d ξ 1, d ξ 2, ... and for all I = So for any positive number ε, there is always

P{ | ξ - Eξ | ≥ ε} ≤ Dξ/ε？

P{ | ξ - Eξ | < ε} ≥ 1 - Dξ/ε？

Where e ξ = σ e ξ i and d ξ = σ d ξ i.

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Let ξi be the number of points thrown at the ith time, where i= 1, 2, 3, 4.

According to the characteristics of random experiments, ξ 1, ξ 2, ξ 3 and ξ 4 are independent of each other, ξ = ξ 1+ξ2+ξ3+ξ4.

However, Eξi = (1+2+3+4+5+6)/6 = 7/2.

Eξi？ = ( 1? +2? +3? +4? +5? +6? )/6 = 9 1/6

So, Dξi = Eξi? - (Eξi)？ = 9 1/6 - (7/2)? = 35/ 12

∴eξ=σeξI = 4 *(7/2)= 14

dξ=σdξI = 4 *(35/ 12)= 35/3

According to Chebyshev's law of large numbers, there are

P( 10