1. 100 5 .
W(A) = 5/100 = 1/20.
2. 25 ' 22 . ³ '
W(A) = 22/25.
. L (). , , L/3. . .
1. . , , 12 . 9 . . , , , .
'
- , 2 .
:
312 = 12! / (12 - 3)! = 12! / 9! = 10 * 11* 12 = 1320.
, , :
() = 3 / 1320 = 1 / 440.
2. , 䳿 - , , 6.
'
6 * 6 = 36 ( -). ( 5) - : (1;5), (5;1), (4;2), (2;4), (3;3).
() = 5 / 36.
3.
1. 50 , 5 - . . , .
':
() = /Σ = 5/50=1/10.
2. . , .
':
() = /Σ = /: 1, 2, 3, 4, 5, 6 → n=6; : 2, 4, 6 → n=3/ = 3/6 = 1/2.
3. 1 100. , 5.
':
() = /Σ = /1 100 → n=100; : 100 - 9=91/ = 91/100 = 0,91.
4. 5 ; : , , , , . , "".
':
N=5, , , : 15 = 5! = 1*2*3*4*5 = 120. . → () = 1/120.
5. 6 : , , , , , . . , , , "".
':
64 = 6! / (6-4)! = 360; () = 1/360.
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6. , 1000 , . , : ) ; ) ; ) .
':
1000 10 . .
) 6, 8*8 → 64*6 = 384; () = 384/1000 = 0,384.
) , "" 3, 32 → 32*3 = 96; () = 96/1000 = 0,096.
) 8 , 3 8; () = 8/1000 = 0,008.
7. (28 ) . , , : ) ; ) .
':
-, :
0-0, 0-1, 0-2, 0-3, 0-4, 0-5, 0-6;
1-1, 1-2, 1-3, 1-4, 1-5, 1-6;
2-2, 2-3, 2-4, 2-5, 2-6;
3-3, 3-4, 3-5, 3-6;
4-4, 4-5, 4-6;
5-5, 5-6;
6-6.
) , 6 . ( - , - ), 27 (n=27). → () = 6 / 27 = 2/9.
) - - 12. → () = 12 / 27 = 4/9.
8. 5 . 6 , . , . , .
':
, 5 65 , :
() = 1 / 65 .
9. ³ . , .
':
8! . , ( - 7 ) → () = 7*(28) = 7* 2!*6!/8! = 1/4.
10. 10 , 5 4 , 3 - 1 , 2 - 2 . , 5 .
':
2 210. : ( 5) 4 ( 1) 1 ., , 15 13 (, ) → () = 15 * 13 / 210 = [(5!/1!*4!)*(3!/1!*2!)] / (10!/ 2!*8!)] = 5 * 3 / 9*10 = 15 / 45 = 1/3.
11. 100 5 . ?
':
W = 5 / 100 = 1/20.
12. 0,85. , 120.
':
W. = n. / n → n. = W. * n = 0,85*120 = 102 ("" ).
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