Soru

Zorluk: OrtaCompound Events and Probability Laws

In a telecommunications network, two independent relay switches, R1R_1 and R2R_2, operate during a data transmission. The probability that switch R1R_1 functions successfully is 0.800.80, and the probability that switch R2R_2 functions successfully is 0.750.75. What is the probability that at least one of the two switches functions successfully during the transmission?

Cevap: 0.95

Cevap

The probability that at least one switch functions successfully is 0.95.
Since the two switches operate independently, the probability of both failing is the product of their individual failure probabilities: (10.80)×(10.75)=0.20×0.25=0.05(1 - 0.80) \times (1 - 0.75) = 0.20 \times 0.25 = 0.05. Therefore, the probability that at least one switch functions successfully is 10.05=0.951 - 0.05 = 0.95. Alternatively, using the addition law for independent events: P(R1R2)=P(R1)+P(R2)P(R1R2)=0.80+0.75(0.80×0.75)=1.550.60=0.95P(R_1 \cup R_2) = P(R_1) + P(R_2) - P(R_1 \cap R_2) = 0.80 + 0.75 - (0.80 \times 0.75) = 1.55 - 0.60 = 0.95.

Adım Adım Çözüm

1
Determine the probabilities of individual switch failure.
P(R_1') = 0.20 and P(R_2') = 0.25
The probability of an event failing is the complement of its success probability: P(E') = 1 - P(E).
2
Compute the probability that both switches fail simultaneously.
P(R_1' ∩ R_2') = 0.20 × 0.25 = 0.05
Since the switches operate independently, the multiplication law for independent events applies: P(A ∩ B) = P(A) × P(B).
3
Calculate the probability that at least one switch functions successfully.
P(at least one) = 1 - 0.05 = 0.95
The complement of 'neither switch functioning' is 'at least one switch functioning'.

Anahtar Kavram

Probability laws for independent compound events and the complement rule
Tahmini Süre:1m 30s
Bu soruyu puanla