I think it would be 29 students in the larger class
Answer:
A) Mean = 1264
Standard deviation = 37
B) CI ≈ (1241, 1287)
Step-by-step explanation:
A) Mean = Σx/n
Σx = 1229 + 1257 + 1243 + 1194 + 1268 + 1316 + 1275 + 1317 + 1275
Σx = 11374
Mean(x¯) = 11374/9
Mean(x¯) ≈ 1264
Standard deviation = √(∑(x - x¯)²/(n)
From online calculator;
Standard deviation; s ≈ 37
B) Our distribution factor is; DF = n - 1 = 9 - 1 = 8
From t-table attached, our critical value at 90% Confidence interval is t = 1.86
Formula for confidence interval is;
CI = x¯ ± t(s/√n)
CI = 1264 ± 1.86(37/√9)
CI = 1264 ± 22.94
CI ≈ (1241, 1287)
Answer:
Step-by-step explanation:
In the two independent samples application, it involves the test of hypothesis that is the difference in population means, μ1 - μ2. The null hypothesis is always that there is no difference between groups with respect to means.
Null hypothesis: ∪₁ = ∪₂. where ∪₁ represent the mean of sample 1 and ∪₂ represent the mean of sample 2.
A researcher can hypothesize that the first mean is larger than the second (H1: μ1 > μ2 ), that the first mean is smaller than the second (H1: μ1 < μ2 ), or that the means are different (H1: μ1 ≠ μ2 ). These ae the alternative hypothesis.
Thus for the z test:
if n₁ > 30 and n₂ > 30
z = X₁ - X₂ / {Sp[√(1/n₁ + 1/n₂)]}
where Sp is √{ [(n₁-1)s₁² + (n₂-1)s₂²] / (n₁+n₂-2)}
Answer:
$0.45.
Step-by-step explanation:
Total amount of money held by all 5 children
= 5 * 0.50 = $2.50.
After 0.25 is lost the total = $2.25.
So the new average = 2.25 / 5
= $0.45.