Answer:
Step-by-step explanation:
Hello!
The objective is to compare if the average time that families live in Gotham and Metropolis, the real state company thinks the average time is less in Gotham than in Metropolis. There are two populations of interest and therefore two variables:
X₁: Time a family has lived in Gotham.
n₁= 100 families
X[bar]₁= 35 months
S₁= 900 days
X₂: Time a family has lived in Metropolis.
n₂= 150 families
X[bar]₂= 50 months
S₂= 1050 days
You are studying the population means of both variables, so you have to work using the distribution of the sample means:
If:
X[bar]₁~N(μ₁;σ₁²/n₁)
X[bar]₂~N(μ₂;σ₂²/n₂)
We can say that the difference between these both distributions will have the following distribution:
(X[bar]₁-X[bar]₂)~N(μ₁-μ₂;σ₁²/n₁+σ₂²/n₂)
The population variance for the difference between the two sample means is:
σ₁²/n₁+σ₂²/n₂
Since both σ₁² = σ₂² = σ² we can say that:
σ² (1/n₁+1/n₂)To study the difference between two normal populations with unknown bu equal population variances the distribution to use is:
The estimation of the standard error of the difference is:
Sa= 992.8423≅ 992.84
The standard error of the difference between the two sample means is 128.18.
I hope this helps!
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The answer would be 0.75 because when you divide the numerator and the denominator the answer would be 0.75
6 and 7. square root is 6.8557
The complete question is
Which statement is true about the factorization of 30x² + 40xy + 51y²<span>?
A. The factorization of the polynomial is 10(3x2 + 4xy + 5y2).
B. The polynomial can be rewritten as the product of a trinomial and xy.
C. The greatest common factor of the polynomial is 51x2y2.
D. The polynomial is prime, and the greatest common factor of the terms is 1.
we know that
case A) </span>is not right because 10 is not a common factor of the three terms.
case B) is not right because the original polynomial is already a trinomial
case C) is not right because the terms do not contain 51x^2y^2
<span>case D) is right
because
</span><span>Factors of 30 are-----> 1,2,3,5,6,10,15,30
</span>Factors of 40 are-----> 1,2,4,5,8,10,20,40
Factors of 51 are-----> 1,51
<span>so
</span><span>The "Greatest Common Factor" is the largest of the common factors
</span><span>the GFC is 1
therefore
the answer is the option
</span>D. The polynomial is prime, and the greatest common factor of the terms is 1<span>
</span>