Answer:
The bulbs should be replaced each 1436.9 hours.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

How often should the bulbs be replaced so that no more than 1% burn out between replacement periods?
This is the first percentile of hours. So it is X when Z has a pvalue of 0.01.
So it is X when Z = -2.33.




The bulbs should be replaced each 1436.9 hours.
49 due to divide and multiply steps
Answer:
whats the question
Step-by-step explanation:
Complete question is;
Andrea is given ABC and told that a² + b² = c². She draws right triangle RTS with legs measuring a and b and hypotenuse measuring 2. Which best describes what Andrea should
do in order to prove that ABC is a right triangle?
Answer:
Andrea should show that c = 2, so: ∡ABC = ∡RTS and ∡C = ∡S. Hence, ∡C is a right angled triangle, hence ΔABC is a right triangle
Step-by-step explanation:
In this question, we are told that the given sides of the triangle are a, b and c. Now, Andrea is able to draw the two sides of the right triangle with sides = a and b and the third, hypotenuse equal to 2. Since the length of the hypotenuse = 2, then we have;
2² = a² + b²
However, we are told that c² = a² + b²
Therefore, c = 2
Hence, Andrea should show that c = 2 so ΔABC = ΔRTS and ∡C = ∡S hence ∡C is a right angled triangle since it is the angle opposite to the hypotenuse c and therefore, ΔABC is a right triangle.
Answer:The correct answer is 2/3x + 17
Step-by-step explanation: