, :
w1 = 7 10 3, w2 = 210 3, w3 = 110 3,
: 50 , , .
1.
w = å wi = (7 + 2 + 1)×10 3 = 0,01.
2.
= 1 / w = 1 / 0,01 = 100 .
3. 50 .
P (t) = e w t = e 0,01×50 = 0,61.
4. ,
D = P2 (t) / P1 (t) = e 0,5 w t = e 0,5×0,01×50 =1,28.
2
= 0,99 1000 . . . , .
1. . , .
QC (t)1 = [1 - PC (t)] = 1 - P1 (t) × P2 (t) × × Pi (t) ×× Pn (t) =
= 1 Pi (t)8 = 1 0,998 = 1 0,923 = 0,077.
2.
QC (t)11 = [1 - PC (t)] = 1 - Pi (t)6 = 1 0,996 = 1 0,942 =0,058.
3. , ( )
D = QC (t)1 / QC (t)11 = 0,077 / 0,058 = 1,328.
3
. t 0,98, 0,99. .
1. , . .
Q (t) = Q1 (t)× Q2 (t) = [1 P (t) ]×[ 1 P (t) ] =
= [1 0,98 ]×[ 1 0,99 ] = 0,0002.
2. t
PC (t) = [1 - QC (t)] = 1 0,0002 = 0,9998.