Answer:
I.
A is a 4 x 5 matrix => A: U -> V, dim U = 5, dim V = 4
Null space is exactly two dimensional plane
dim null (A) = 2
II.
Rank A = dim U - dim Null A = 5 - 2 = 3
III.
Number of linearly Independent columns of A is the rank of A = 3
IV.
Yes, The system Ax = b has no solution sometimes as range of A \neq V
V.
Yes,Sometimes Ax = b has a unique solution
VI.
Yes, sometimes Ax = b has infinitely many solutions
In an arithmetic sequence:
Tn=t₁+(n-1)d
t₄=t₁+(4-1)d=t₁+3d
t₅=t₁+(5-1)d=t₁+4d
t₆=t₁+(6-1)d=t₁+5d
t₄+t₅+t₆=(t₁+3d) +(t₁+4d)+(t₁+5d)=3t₁+12d
Therefore:
3t₁+12d=300 (1)
t₁₅=t₁+(15-1)d=t₁+14d
t₁₆=t₁+(16-1)d=t₁+15d
t₁₇=t₁+(17-1)d=t₁+16d
t₁₅+t₁₆+t₁₇=(t₁+14d)+(t₁+15d)+(t₁+16d)=3t₁+45d
Therefore:
3t₁+45d=201 (2)
With the equations (1) and (2) we make an system of equations:
3t₁+12d=300
3t₁+45d=201
we can solve this system of equations by reduction method.
3t₁+12d=300
-(3t₁+45d=201)
-----------------------------
-33d=99 ⇒d=99/-33=-3
3t₁+12d=300
3t₁+12(-3)=300
3t₁-36=300
3t₁=300+36
3t₁=336
t₁=336/3
t₁=112
Threfore:
Tn=112+(n-1)(-3)
Tn=112-3n+3
Tn=115-3n
Now, we calculate T₁₈:
T₁₈=115-3(18)=115-54=61
Answer: T₁₈=61
2
42 ÷ 2 = 21
16 ÷ 2 = 8
Let's try the other factors of 42...
42 ÷ 6 = 7
16 ÷ 6 = 2.66
No...
42 ÷ 7 = 6
16 ÷ 7 = 2 2/7
No...
42 ÷ 14 = 3
16 ÷ 14 = 1.1428
No...
Answer:
Standard error = 0.070
Step-by-step explanation:
Formula for the standard error of the distribution of differences in sample proportions is;
σ_(A - B) = √((p_a^(1 - p_a^)/n_a) + (p_b^(1 - p_b^)/n_b))
We are given;
p_a^ = 0.48
n_a = 80
p_b^ = 0.13
n_b = 66
Thus;
σ_(A - B) = √((0.48(1 - 0.48)/80) + (0.14(1 - 0.13)/66))
σ_(A - B) = √0.00496545455
σ_(A - B) = 0.070
