I'm learning the exact same thing so give me some question and I can see what I can do!
solution:
The variable is discrete because it is countable.
The number5 of lightning strikes in a city in one year is countable value.
So, it is discrete
I think it's 1.90. I am not fully sure about the answer if it's wrong.
First we will do -3 times everything in the parenthesis.
-3 times -4n = 12n
-3 times 30 = -90
SO,
12n - 90 = -30
+90 +90
12n = 60
divide 12 on both sides;
n = 5
This is your answer,
IF THIS HELPED, PLS GIVE ME BRAINLIEST!
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
</span>
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>