Answer:
Step-by-step explanation:
The first thing that we can do is look at the equation of the line and then worry about the inequality afterwards.
This line has a y-intercept of 4 and a slope of -1.
This means that the equation of this line would be 
Now that we have the equation of the line, we just need to determine which inequality sign to use.
As the shaded region is BELOW the line, we will use a less than (<) sign.
As the line is fully shaded, I can only assume that it is meant to include the line, which would mean that
would be the equation for this inequality.
Answer:
a) The probability of a pregnancy lasting X days or longer is given by 1 subtracted by the p-value of
, in which
is the mean and
is the standard deviation.
b) We have to find X when Z has a p-value of
, and X is given by:
, in which
is the mean and
is the standard deviation.
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.
In this question:
Mean
, standard deviation 
a. Find the probability of a pregnancy lasting X days or longer.
The probability of a pregnancy lasting X days or longer is given by 1 subtracted by the p-value of
, in which
is the mean and
is the standard deviation.
b. If the length of pregnancy is in the lowest a%, then the baby is premature. Find the length that separates premature babies from those who are not premature.
We have to find X when Z has a p-value of
, and X is given by:
, in which
is the mean and
is the standard deviation.
Part A: First, list multiples for each number. The multiples of 5 are: 5, 10, 15, 20, 25 30, 35, 40, 45, 50, 55, 60, etc. The multiples of 12 are: 12, 24, 36,48, 60, etc. The least common multiple is the first common multiple between the two, in this case being 60. The LCM of 5 and 12 is 60.
Part B: SImilar to above, list all factors for each number. 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, and 72. 81: 1, 3, 9, 27, and 81. The greatest common factor is the highest common number, 9 in this case. The GCF of 72 and 81 is 9.
Part C: To rewrite, we need to take out the 9 by dividing. 72/9 is 8. 81/9 is 9. Therefore, we would get 9(8+9), to equal 153. Your answer here is 9( 8 + 9 ). Hope this helped!