X=c/r make the r as a subject

A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized below

jok3333 [9.3K]

Answer:

The value of the test statistic = 2.58

Test statistic Z = - 4.805

|Z| = 4.805 > 2.58

Null hypothesis is rejected The value of the test statistic = 2.58

There is significant difference between in the mean number of times men and women send a Twitter message in a day

Step-by-step explanation:

Step(i):-

Sample size of men n₁ = 25

mean of the first sample x₁⁻ = 20

Standard deviation of the first sample σ₁ = 5

Sample size of women n₂ = 30

mean of the second sample x₂⁻ = 30

Standard deviation of the first sample σ₂ = 10

Level of significance ∝= 0.01

Step(ii):-

Null Hypothesis : H₀: There is no significant difference between in the mean number of times men and women send a Twitter message in a day

Alternative Hypothesis :H₁:There is significant difference between in the mean number of times men and women send a Twitter message in a day

Test statistic

$Z = \frac{x^{-} _{1} - x^{-} _{2} }{\sqrt{\frac{S.D_{1} ^{2} }{n_{1} }+\frac{ S.D_{2} ^{2}}{n_{2} } } }$

$Z = \frac{20 - 30 }{\sqrt{\frac{(5)^{2} }{25 }+\frac{ (10)^{2} }{ 30} } }$

Z = $\frac{-10}{2.081} = - 4.805$

The value of the test statistic = 2.58 C

|Z| = 4.805 > 2.58

Null hypothesis is rejected The value of the test statistic = 2.58

Conclusion:-

There is significant difference between in the mean number of times men and women send a Twitter message in a day

7 0

3 years ago

Explain how you would use algebra tiles to solve x - 3 = 7

Andrew [12]

Answer:

Start by laying out 7 tiles, and then adding 3. Whatever that number of tiles is equals x.

x = 10

10 - 3 = 7

7 0

3 years ago

Read 2 more answers

How to find the surface area

Stolb23 [73]

Answer:

158 in²

Step-by-step explanation:

Surface area

A = 2·(l·w + l·h + w·h)

= 2·(3in·8in + 8in·5in + 3in·5in)

= 2·(24in² + 40in² + 15in²)

= 2·(79in²)

= 158 in²

al3xis

8 0

3 years ago

Question 12 (1 point) Given P(A) 0.34, P(A and B) 0.27, P(A or B) 0.44, what is P(B)? Answer in decimal form. Round to 2 decimal

Tema [17]

Answer: The required probability of event B is P(B) = 0.37.

Step-by-step explanation: For two events A and B, we are given the following probabilities :

P(A) = 0.34, P(A ∩ B) = 0.27 and P(A ∪ B) = 0.44.

We are to find the probability of event B, P(B) = ?

From the laws of probability, we have

$P(A\cup B)=P(A)+P(B)-P(A\cap B)\\\\\Rightarrow 0.44=0.34+P(B)-0.27\\\\\Rightarrow 0.44=0.07+P(B)\\\\\Rightarrow P(B)=0.44-0.07\\\\\Rightarrow P(B)=0.37.$

Thus, the required probability of event B is P(B) = 0.37.

6 0

3 years ago

Jamal hiked on two trails. The first trail was 3 1/3 miles long, and the second trail was 1 3/5 times as long as the first trail

monitta

The answer is 6.6 repeating, so 6.6666...

So first I took 1 and 3/5 and put it into decimal form which gave us 1.6, then I did the same with 3 and 1/3 and got 3.3 repeating, and now I multiply these and get 5.33333 repeating, and now I add the 3 and 1/3rd to get 6.6666 repeating.

8 0

3 years ago