<span>the probability of an event and the probability of its complement add up to 1
because the total events are the even it self and its compliment, so its probability equal to 1 because these are all the possible events that will occur. for example a coin toss, an event head will happen 0.5, and its complement is tails which will also happens 0.5</span>
Option 1:
<span>Measuring the heights of every fiftieth person on the school roster to determine the average heights of the boys in the school
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Comment: this might not be a good idea for fairness as we only wish to determine average height of the boys. Taking a group of 50 people randomly, might not give us the same number of boys every time.
Option 2:
<span>Calling every third person on the soccer team’s roster to determine how many of the team members have completed their fundraising assignment
Comment: The context doesn't seem to need a sampling. The number of players in a soccer team is considerably small. We can find exact data by asking in person.
Option 3:
</span><span>
Observing every person walking down Main Street at 5 p.m. one evening to determine the percentage of people who wear glasses
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Comment: To get a more accurate result and fairer sampling, the period of observing could have been longer, for example, observing for 12 hours on that day, or an alternative is to observe at 5 pm for 7 days in a row. It could happen that no one walking down the Main street precisely at 5 pm wears glasses, or it could happen the other way around.
Option 4:
<span>Sending a confidential e-mail survey to every one-hundredth parent in the school district to determine the overall satisfaction of the residents of the town taking a poll in the lunch room (where all students currently have to eat lunch) to determine the number of students who want to be able to leave campus during lunch.
Comment: This sampling does fairly represent the population, although it might be an idea to scale down the sample population, i.e. every fiftieth parent.
Answer: Option 4</span>
You forgot to include the statements for us to choose from.
3x+2y=22
3x-2y=2
we add these to equations together
6x=24
x=4
then we plug in x to find y
3*4+2y=22
12+2y=22
2y=10
y=5
solution is (4,5) (x=4 and y=5)
Answer:
The answer is the 2nd box down, 20x⁷
