Let area of triangle AEC = x
Area of triangle BAC = 1/2 * 15 * 12 = 90
Area of triangle DCA = 1/2 * 15 * 6 = 45
90 = p + x and
45 = q + x Subtracting the 2 equations:-
90 - 45 = p - q
Answer p - q = 45
17/2 = 8.5 hours per week
8.5 x 5 = 42.5 hours in 5 weeks
Answer: 208.
Step-by-step explanation:
The formula to find the minimum sample size is given by :-
(1)
, where z* = critical z-value (two tailed).
= Standard deviation ( from prior study ) and E = Margin of error.
As per given , we have
Margin of error : E= 0.29
Confidence level = 85%
Significance level =
Using z-table , the critical value (two -tailed)=
As per previous study , Variance =
Now, the required minimum sample size = 
[Substitute the values in formula (1)]
[ Round to the next integer]
Hence, the minimum number of third graders that must be included in a sample = 208.
Basically the question is asking you for the area of the triangle.
The formula to find the area of a triangle is base x height divided by 2.
So in this case you would do 27 x 15.5 = 418.5
Now you divide by 2 (209.25)
So the answer is D. Hope this helps!!
