PLEASE HELP ASAP WILL GIVE BRAINLIEST ALGEBRA 2

Is 4/100 greater than 0.2

balu736 [363]

Answer:

No

Step-by-step explanation:

4/100 = 0.04

0.04<0.2

4 0

4 years ago

A survey found that 73% of adults have a landline at their residence (event A); 83% have a cell phone (event B). It is known tha

4vir4ik [10]

Answer:

3. What is the probability that an adult selected at random has both a landline and a cell phone?

A. 0.58

4. Given an adult has a cell phone, what is the probability he does not have a landline?

C. 0.3012

Step-by-step explanation:

We solve this problem building the Venn's diagram of these probabilities.

I am going to say that:

A is the probability that an adult has a landline at his residence.

B is the probability that an adult has a cell phone.

C is the probability that a mean is neither of those.

We have that:

$A = a + (A \cap B)$

In which a is the probability that an adult has a landline but not a cell phone and $A \cap B$ is the probability that an adult has both of these things.

By the same logic, we have that:

$B = b + (A \cap B)$

The sum of all the subsets is 1:

$a + b + (A \cap B) + C = 1$

2% of adults have neither a cell phone nor a landline.

This means that $C = 0.02$ .

73% of adults have a landline at their residence (event A); 83% have a cell phone (event B)

So $A = 0.73, B = 0.83$ .

What is the probability that an adult selected at random has both a landline and a cell phone?

This is $A \cap B$ .

We have that $A = 0.73$ . So

$A = a + (A \cap B)$

$a = 0.73 - (A \cap B)$

By the same logic, we have that:

$b = 0.83 - (A \cap B)$ .

So

$a + b + (A \cap B) + C = 1$

$0.73 - (A \cap B) + 0.83 - (A \cap B) + (A \cap B) + 0.02 = 1$

$(A \cap B) = 0.75 + 0.83 - 1 = 0.58$

So the answer for question 3 is A.

4. Given an adult has a cell phone, what is the probability he does not have a landline?

83% of the adults have a cellphone.

We have that

$b = B - (A \cap B) = 0.83 - 0.58 = 0.25$

25% of those do not have a landline.

So $P = \frac{0.25}{0.83} = 0.3012$

The answer for question 4 is C.

4 0

3 years ago

What is the focus of the parabola? y=−1/4x^2−x+3

Delvig [45]

We know that
the equation of the parabola is of the form
y=ax²+bx+c

in this problem
y=−1/4x²<span>−x+3
where
a=-1/4
b=-1
c=3

</span><span> the coordinates of the focus are
</span>
(-b/2a,(1-D)/4a)
where
D is the discriminant b²-4ac
D=(-1)²-4*(-1/4)*3-----> D=1+3---> D=4
therefore
x coordinate of the focus
-b/2a----> 1/[2*(-1/4)]----> -2

y coordinate of the focus
(1-D)/4a------> (1-4)/(-4/4)---> 3

the coordinates of the focus are
(-2,3)

5 0

3 years ago

A local weather enthusiast wants to see if the last five summers have been warmer than normal for Eloy, Arizona. From the Nation

lys-0071 [83]

Answer:

Step-by-step explanation:

This is a question on hypothesis testing.

Population mean based on 30 year average for July was 90 with

a std deviation of 2.1

Sample of 5 shows average 93.5

To check whether sample average = population average

H0: x bar =90

Ha: x bar not equal 90(Two tailed test)

Test statistic = $\frac{93.5-90}{\frac{2.1}{\sqrt{5} } }$

=3.73

Since this lies outside the range (-1.96, 1.96) we reject null hypothesis

Hence we cannot say sample mean equals 90

5 0

3 years ago

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Which method would determine the volume of the prism with dimensions 2 times 2 and one-fourth times 4 shown below?

gladu [14]

Answer:

<h2>THE CORRECT ANSWERS (B.)</h2>

Step-by-step explanation:

8 0

3 years ago

Read 2 more answers