Answer:
a) 0.4164
Step-by-step explanation:
Mean lifespan (μ) = 18.8 days
Standard deviation (σ) = 2 days
For any given lifespan 'X', the z-score is:
For X=12.04 days:
A z-score of -3.38 falls in the 0.036-th percentile of a normal distribution.
For X=18.38 days:
A z-score of -3.38 falls in the 41.68th percentile of a normal distribution.
The probability that a butterfly lives between 12.04 and 18.38 days is
Ok to solve this just write it out how it sounds, like so.
3x/4
-16
Hope this helps!=)
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.
The series of numbers is adding 5 and then subtracting 2
20+5=25
25-2=23
23+5=28
28-2=26
and so on. Do you understand?
First, we can factor this to make it easier to solve:
3(x^3 + 13x^2 + 13x + 9)
Now, we can use the rational root theorem like so:
List factors of 9:
1, 3, 9.
List factors of 1:
1
Because of this, we know our possible rational roots are:
+/-1, +/-3, +/-9
If none of these zeros fit using the remainder theorem, then we know our roots will be irrational.
