Answer:
18.75 percent
Step-by-step explanation:
150 / 800 x 100 = 18.75
Answer:
around 230
Step-by-step explanation:
91+122+478=691
691÷3= 230.33333333
Answer:
2sin50 cos20
Step-by-step explanation:
We need to write sin (70) + sin(30) as a product. The formula used here is :

Here, A = 70 and B = 30
So,

So, the value of sin (70) + sin(30) is 2sin50 cos20. Hence, the correct option is (c).
Answer:
--- Standard deviation
Step-by-step explanation:
Given
See attachment for graph
Solving (a): Explain how the standard deviation is calculated.
<u>Start by calculating the mean</u>
To do this, we divide the sum of the products of grade and number of students by the total number of students;
i.e.

So, we have:



Next, calculate the variance using the following formula:

i.e subtract the mean from each dataset; take the squares; add up the squares; then divide the sum by the number of dataset
So, we have:



Lastly, take the square root of the variance to get the standard deviation


--- approximated
<em>Hence, the standard deviation is approximately 11.28</em>
Considering the calculated mean (i.e. 82.76), the standard deviation (i.e. 11.28) is small and this means that the grade of the students are close to the average grade.
Answer:
The area of the shaded region is 0.2898.
Step-by-step explanation:
Let <em>X</em> represent the IQ scores of adults.
It is provided that
.
Compute the probability of an adult having an IQ between 106 and 124 as follows:

*Use a <em>z</em>-table.
Thus, the area of the shaded region is 0.2898.