Answer:
$7.88
Step-by-step explanation:
87.56*0.09=7.88
How many males and how many females would there be if the total enrollment is 15000?
Ratio is
90 males 15000 - x
------------- = ---------------
125 fem x
Then 90x = 1875000 - 125x, or 215x = 1875000
x = approx 8720 females
and 15000-8720, or 6279 males
If every male finds a dance partner, that would leave (8720-6279) females, or 2440, without dance partners. ;(
Check: is the male:female ratio near 90:125?
Is 6279:8720 approx equal to 90:125?
Yes. 0.72 (approx) = 0.72 (approx).
Answer:
d. Approximate the standard normal distribution with the Student's t distribution
(0.2199 ; 0.2327)
Step-by-step explanation:
Given that :
Sample size, n = 31
Sample mean, xbar = 0.2258
Sample standard deviation, s = 0.0188
Confidence interval (C. I) :
xbar ± margin of error
Margin of Error : Tcritical * s/sqrt(n)
Degree of freedom, df = n - 1 = 31 - 1 = 30
Tcritical value :
T0.05/2, 30 = 2.042
Margin of Error = 2.042 * 0.0188/sqrt(31)
Margin of Error = 0.0068949
C. I = 0.2258 ± 0.0068949
Lower boundary : (0.2258 - 0.006895) = 0.2189
Upper boundary : (0.2258 - 0.006895) = 0.2327
(0.2199 ; 0.2327)
It will either be 0.28 or 0,42 depending of what 12-8 means