The following table contains the probability distribution for X = the number of retransmissions necessary to successfully transmit a 1024K data package through a double satellite media.
X
0
1
2
3
P(X)
0.35
0.25
***
0.15
The mean or expected value for the number of retransmissions is?
1.2
1.0
1.5
2.25
Calculating the mean or expected value for the number of retransmissions:
E(X) = Σ X * P(X)
E(X) = (0 * 0.35) + (1 * 0.25) + (2 * 0.15) + (3 * 0.25)
E(X) = 0 + 0.25 + 0.3 + 0.75
E(X) = 1.3
Therefore, the mean or expected value for the number of retransmissions is 1.3.