5/6 is not the definite ratio, when you take a larger sample size it could be off by a bit like 499/600 or 501/600
Answer:
Hello! answer: 13
Step-by-step explanation:
-4 × 13 = 52 therefore a = 13 HOPE THAT HELPS!
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>
Answer:
B
Step-by-step explanation:
Also solved eveything
(x+9)^2=49
x^2+18x+81=49
x^2+18x+32=0
a=1, b=18 and c=32
x= (-18 +/- Sqrt (18^2-4×32))/2
x= (-18 +/- Sqrt (324-128))/2
x= (-18 +/- Sqrt (196))/2
x= (-18 +/- 14)/2
x= (-18 +14)/2 = -4/2 =-2
OR
x= (-18 -14)/2 = -32/2 =-16
Answer:
r = 9
Step-by-step explanation:
cross multiply
9 * r = 81
9r = 81
divide both sides by 9
r= 81/9
r = 9
