Answer:
a) 
b) The should sample at least 293 small claims.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so
, which means that the answer of question a is z = 1.645.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.
(b) If the group wants their estimate to have a maximum error of $12, how many small claims should they sample?
They should sample at least n small claims, in which n is found when
. So







The should sample at least 293 small claims.
Answer:
a = 4, x = 1
Step-by-step explanation:
The opposite sides of a parallelogram are congruent , then
WX = YZ , that is
a² + 5a = 5a + 16 ( subtract 5a from both sides )
a² = 16 ( take the square root of both sides )
a = ±
= ± 4
Since a > 0 , then a = 4
Also
XY = WZ , that is
x² + 6x = 4x + 3 ( subtract 4x + 3 from both sides )
x² + 2x - 3 = 0 ← in standard form
(x + 3)(x - 1) = 0 ← in factored form
Equate each factor to zero and solve for x
x + 3 = 0 ⇒ x = - 3
x - 1 = 0 ⇒ x = 1
Since x > 0 , then x = 1
Answer:
dx/dt = 5√5/2
Step-by-step explanation:
Given:
dx/dt = 25 feet per second
According to Pythagoras theorem:
x² + 90² = y²
We know that x = 30 ft
So,
x² + 90² = y²
30² + 90² = y²
y = 30√10
So,
x² + 90² = y²
By taking differentiate:
2x dx/dt = 2y dy/dt
[x/y][dx/dt] = dy/dt
dx/dt = 5√5/2
A1=8
a2=12
a3=18
a4=27
a5=40.5
a6=60.75