Answer:
609
Step-by-step explanation:
Standard deviation = = $30
Margin of error = E = $2
Confidence level = 90%
Since the distribution is said to be normal, we will use z scores to solve this problem.
The z score for 90% confidence level = z = 1.645
Sample size= n = ?
The formula to calculate the margin of error is:
Using the values in above equation, we get:
This means, the minimum number of observations required is 609
Options:
a. Nikki's proposed placement will light a greater area than Dylan's placement.
b. Dylan's proposed placement will light a greater area than Nikki's placement.
c. Both proposed placements will light the same sized area.
d. Nikki's proposed placement will light more than half the yard.
e. Dylan's proposed placement will light more than half the yard.
f. Dylan's proposed placement will light exactly half of the yard.
g. Nikki's proposed placement will light less than half of the yard.
Answer:
C) Both proposed placements will light the same sized area.
F) Dylan's proposed placement will light exactly half of the yard.
Step-by-step explanation:
The area of a triangle is (base x height) / 2, and both lights illuminate the same base and height = (60 x 38) / 2 = 1,140 sq ft
Both Dylan's and Nikki's proposed placement will lit exactly half of the yard. The yard's total area = 60 x 38 = 2,280 sq ft, which is twice the area lit by the lights.
