Answer:
Yup that's a scientific number alright.
Multiply both sides by c
X = d*c
Answer:
P = 0.006
Step-by-step explanation:
Given
n = 25 Lamps
each with mean lifetime of 50 hours and standard deviation (SD) of 4 hours
Find probability that the lamp will be burning at end of 1300 hours period.
As we are not given that exact lamp, it means we have to find the probability where any of the lamp burning at the end of 1300 hours, So we have
Suppose i represents lamps
P (∑i from 1 to 25 ( > 1300)) = 1300
= P(> ) where represents mean time of a single lamp
= P (Z> ) Z is the standard normal distribution which can be found by using the formula
Z = Mean Time () - Life time of each Lamp (50 hours)/ (SD/)
Z = (52-50)/(4/) = 2.5
Now, P(Z>2.5) = 0.006 using the standard normal distribution table
Probability that a lamp will be burning at the end of 1300 hours period is 0.006
706,421 rounded to the nearest thousand is 706,000 because the 421 is less than 500 so the 6 would remain a 6.