Answer:
Step-by-step explanation:
<u>Simplify:</u>
- √5(√8 + √18) =
- √5*8 + √5*18 =
- √40 + √90 =
- √4*10 + √9*10 =
- 2√10 + 3√10 =
- (2 + 3)√10 =
- 5√10
<u>The value of a:</u>
Given:
A right angle triangle with angles 45, 45, 90 degrees.
Hypotenuse of the triangle =
mm
Base of the triangle = t
To find:
The value of t.
Solution:
In a right angle triangle,

Using this trigonometric ratio in the given triangle, we get




Therefore, the value of t is 7 millimetres.
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
</span>
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>