Can Someone Assist Me Please? It would be much appreciated
1 answer:
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Answer:
The probability that a randomly chosen light bulb will last less than 900 hours is 0.1587.
Step-by-step explanation:
The life span of these light bulbs is normally distributed with a mean of 1000 hours and a standard deviation of 100 hours
Mean =
Standard deviation =
We are supposed to find the probability that a randomly chosen light bulb will last less than 900 hours.i.e. P(x<900)
So,
Z=-1
P(x<900)=P(z<-1)=0.1587
Hence the probability that a randomly chosen light bulb will last less than 900 hours is 0.1587.
Answer:
The common difference of the progression is 3.
Step-by-step explanation:
Given:
First term of the AP = (a) = -8
Ratio of 7th and 9th term = 5:8
So,
General term of an AP, Tn= a+(n-1)d
Where 'd' is the common difference.
equation...(i)
equation...(ii)
According to the question.
⇒ ...cross-multiplying the terms.
⇒
⇒
⇒ ...subtracting 40d and adding 64 both sides.
⇒
⇒ ...dividing both sides with 3.
So the common difference of the progression is 'd' = 3.