Answer:
0.8413 = 84.13% probability of a bulb lasting for at most 605 hours.
Step-by-step explanation:
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean 
and standard deviation 
, the z-score of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
The standard deviation of the lifetime is 15 hours and the mean lifetime of a bulb is 590 hours.
This means that 
Find the probability of a bulb lasting for at most 605 hours.
This is the pvalue of Z when X = 605. So
has a pvalue of 0.8413
0.8413 = 84.13% probability of a bulb lasting for at most 605 hours.
Answer:
a) 6 2/5
b) 13 1/2
Step-by-step explanation:
Have a nice day!
Can I maybe have brainliest?
I forgot it was simplify..
<span>For a parallelogram to be proven to be a rectange, the opposide sides must be parallel and the two adjacent sides must be perpendicular.
For two parallel sides, the slope of the two sides is equal.
Thus, for the parallelogram to be a rectangle, AB is parallel to CD.
The slope of AB = (y2 - y1)/(x2 - x1) while the slope of CD = (y4 - y3)/(x4 - x3)
Also, BC is perpedicular to CD.
For two perpendicular sides, the product of the slopes is -1.
The slope of BC is given by (y3 - y2)/(x3 - x2).
Therefore, for the parallelogram to be a rectangle.
(y2 - y1)/(x2 - x1) = (y4 - y3)/(x4 - x3) and (y4 - y3)/(x4 - x3) x (y3 - y2)/(x3 - x2) = -1.
The third option is the correct answer.</span>
Answer: the rate at which its altitude is changing is -47 ft/s
Step-by-step explanation:
Given that;
ds/dt = 45 mph = 45 × 5280/3600 = 66 ft/sec
no we have to determine dx/dt
so
cos∅ = dx/dt / ds/dt
cos45° = dx/dt / 66
dx/dt = 0.7071 × 66
dx/dt = 46.6686 ≈ 47 ft/s ( as altitude is decreasing, its negative - )
so the rate at which its altitude is changing is -47 ft/s
Can you help me in my recent
