A new lightbulb has been developed with a mean lifetime of 1800 hours and standard deviation of 100 hours. A sample of 100 of these bulbs is tested. The sample mean lifetime is 1770 hours. (a) What is the probability of obtaining a sample mean that is less than or equal to 1770 hours? (5 points) (b) Would it be unusual to obtain a sample mean of less than or equal to 1770 hours? (5 pts

a) The probability of obtaining a sample mean that is less than or equal to 1770 hours is P(M≤1770)=0.0013.

b) It is unusual, as there are only 13 chances in 10,000 (0.13%) of having this outcome.

Step-by-step explanation:

We have a population lifetime with mean of 1800 hours and standard deviation of 100 hours.

Samples of size n=100 are taken and tested.

We can calculate the probability of obtaining a sample mean that is less than or equal to 1770 hours using a z-score for the sample Mean M=1770 and then calculating its probability according to the standard normal distribution:

d

step-by-step explanation:

by observation, we can see that the the graph is simply the graph of y = |x| that has been shifted 4 units downwards and 3 units to the left.

we can recognize in choice d :

y = | x + 3 |   - 4 (rewriting in general form)

y = | x - (- 3) |   - 4

the "-4 " term means   that the graph has been shifted by 4 units in the negative y direction

the "-3 " term means   that the graph has been shifted by 3 units in the negative x direction

this matches our observation of the graph described above.

idk man good luck man