Answer:
32
Step-by-step explanation:
n(A∪B)=n(A)+n(B)−n(A∩B)−−−−−−−(1)
Given n(A)= ? we represent with x
n(B)= 16
n(A∪B) = 32
Substituting in equation 1 to get n(A)
32 = n(A) + 9 − 9
⇒n(A) = 32 − 0
n(A) = 32
to confirm this we put the values into the formula below
n(A∪B)=n(A)+n(B)−n(A∩B)−−−−−−−(1)
32 = 32 + 9 - 9
Answer: 209
Step-by-step explanation:
Answer:
He has earned $31.25 for his basketball team.
Step-by-step explanation:
25 * 1.25 = 31.25
Since in this case we are
only using the variance of the sample and not the variance of the real population,
therefore we use the t statistic. The formula for the confidence interval is:
<span>CI = X ± t * s / sqrt(n) ---> 1</span>
Where,
X = the sample mean = 84
t = the t score which is
obtained in the standard distribution tables at 95% confidence level
s = sample variance = 12.25
n = number of samples = 49
From the table at 95%
confidence interval and degrees of freedom of 48 (DOF = n -1), the value of t
is around:
t = 1.68
Therefore substituting the
given values to equation 1:
CI = 84 ± 1.68 * 12.25 /
sqrt(49)
CI = 84 ± 2.94
CI = 81.06, 86.94
<span>Therefore at 95% confidence
level, the scores is from 81 to 87.</span>
