Answer:
14 mm squared is the area
Step-by-step explanation:
Plug 50 into y and find x.
5x + 10 (50) = 800
5x + 500 = 800
5x = 800 - 500
5x = 300
x = 300 ÷ 5
x = 60
Margin of error, e = Z*SD/Sqrt (N), where N = Sample population
Assuming a 95% confidence interval and substituting all the values;
At 95% confidence, Z = 1.96
Therefore,
0.23 = 1.96*1.9/Sqrt (N)
Sqrt (N) = 1.96*1.9/0.23
N = (1.96*1.9/0.23)^2 = 262.16 ≈ 263
Minimum sample size required is 263 students.