Answer:
B
Step-by-step explanation:
The recommended sample size n for point estimates is:
n = NX / (N + X - 1)
where N is the population size, and X is defined as:
X = Z² p (1 - p) / E²
where Z is the critical value, p is the sample proportion, and E is the margin of error.
Assume a confidence level of level of 95% and a margin of error of 5%.
α = 0.05, Z(α/2) = 1.96
E = 0.05
Of the 40 units tested, 2 had lifespans less than 26 days. So the proportion is:
p = 2/40 = 0.05
Therefore:
X = (1.96)² (0.05) (1 - 0.05) / (0.05)²
X = 73
Given N = 2000:
n = (2000) (73) / (2000 + 73 - 1)
n = 70.45
Rounding, the recommended sample size is 70.
Answer:
i very diffucult question
Answer:
Answer:
Length of leg of triangle =
Step-by-step explanation:
We are given a 45°-45°-90° triangle with hypotenuse measuring 18 cm.
Let us assume the following labeling of the diagram, as attached in the answer area.
The two angles here are equal to 45° so two sides of the triangle opposite to the equal angles will also be equal to each other i.e. it is an isosceles triangle.
i.e. The sides XY and YZ will be equal.
Let XY = YZ = x cm
It is known that in a right angled triangle, pythagorean theorem holds well.
As per pythagoream theorem:
Putting the values:
So, the length of leg of triangle =
Step-by-step explanation: