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:
4ab² + 20b - 3a
Step-by-step explanation:
This question most likely asks us to simplify the expression, as factoring is not possible...
(ab² + 13b - 4a) + (3ab² + a + 7b),
ab² + 13b - 4a + 3ab² + a + 7b,
ab² + 3ab² + 13b + 7b - 4a + a,
Solution : 4ab² + 20b - 3a
The triangle angle sum theorem states that the 3 angles in the triangle must equal 180 degrees.
Answer:
1. 1.5 inches per minute
2. 90 inches per hour
Step-by-step explanation:
speed =
1. total distance covered = +
=
=
= 4 inches
Total time taken = +
=
=
= 3 minutes
The ants average speed =
= 1
= 1.5
The ants speed is 1 inches per minute.
2. Since;
60 minutes = 1 hour
3 minutes = x hours
x =
=
= 0.05 hours
Speed =
= 90 inches per hour
The red ants speed is 90 inches per hour.
Answer:
i think it will be 0 .....