Answer:
Step-by-step explanation:
Given that :
μ1 = 39420 ; σ1 = 1659 ; s1 = 12
μ2 = 30215 ; σ2 = 4116 ; s2 = 26
df1 = 12 - 1 = 11
df2 = 26 - 1 = 25
98 % confidence interval of the difference in sample means :
Pooled Variance :
S²p = ((df1 * s1²) + (df2 * s2²)) / (df1 + df2)
((11×1659^2)+(25×4116^2))÷(11+25) = 12605874.75
Standard Error :
√(S²p/n1) + (S²p/n2)
√(12605874.75/12) + (12605874.75/26)
= 1239.0847
Answer:A
Step-by-step explanation:positive is bigger then negative.
The answer to your question is arithmetic
