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:

Step-by-step explanation:
Suppose we have a triangle WXY whose internal angles are:



The sum of the measures of the angles must be 180°, thus:

Simplifying:
15x + 15 = 180
Subtracting 15:
15x = 165
Dividing by 15:
x = 11
Thus, the measure of angle Y is


Link is scam dont put it in
Answer:
x = the number
Step-by-step explanation:
15.) 2x + 9 = 25
16.) 3x - 6 = 21
17.) 7x = 12 + 3x
18.) 4x = 18 + x
19.) 2x + 24 = 8x
20.) 30 - x = 4x
Answer:70 passengers are left
Step-by-step explanation:
Started with 51 passengers
Makes formula
51 - 26 + 45 = 70 passengers
Started - left = people left or gained