Please help me out I need it done ASAP

The brand manager for a brand toothpaste must plan a campaign designed to increase brand recognition. He wants to first determin

bulgar [2K]

We need to find out how many adults must the brand manager survey in order to be 90% confident that his estimate is within five percentage points of the true population percentage.

From the given data we know that our confidence level is 90%. From Standard Normal Table we know that the critical level at 90% confidence level is 1.645. In other words, $Z_{Critical}=1.645$ .

We also know that E=5% or E=0.05

Also, since, $\hat{p}$ is not given, we will assume that $\hat{p}$ =0.5. This is because, the formula that we use will have $\hat{p}(1-\hat{p})$ in the expression and that will be maximum only when $\hat{p}$ =0.5. (For any other value of $\hat{p}$ , we will get a value less than 0.25. For example if, $\hat{p}$ is 0.4, then $1-\hat{p}=0.6$ and thus, $\hat{p}(1-\hat{p})=0.24$ .).

We will now use the formula

$n=(\frac{Z_{Critical}}{E})^2\hat{p}(1-\hat{p})$

We will now substitute all the data that we have and we will get

$n=(\frac{1.645}{0.05})^2\times0.5(1-0.5)$

$n=(32.9)^2\times0.25$

$n=270.6025$

which can approximated to n=271.

So, the brand manager needs a sample size of 271

3 0

3 years ago

A company is developing a new high-performance wax for cross country ski racing. In order to justify the price marketing wants,

andrew11 [14]

Answer:

A)Yes they should market the wax, because it melts before 55 seconds

C) Null hypothesis: mean <55 vs. Alternative hypothesis :mean =55

D) the value is 51.33 seconds

Step-by-step explanation:

The selected samples for the champion are : 57.9, 62.9, 50.6, 50.5,48.2,47.2,50.2 and 43.1

The mean is ;

Sum =57.9 + 62.9 + 50.6 + 50.5+48.2+47.2+50.2+ 43.1 =410.6

Mean= 410.6/8 =51.33= mean

Assuming Significant =0.05 thus applying this level will give you 51.28-51.38

if specifically, the mean time to finish their standard test course should be less than 55 seconds for a former Olympic champion, then the null hypothesis is correct

Then;

Null hypothesis: mean <55

Alternative hypothesis :mean =55

7 0

3 years ago

Convert the rectangular coordinates (4√3,−4) to polar form. Let r>0 and 0≤θ<2π.

spayn [35]

Answer:

(8,150)

Step-by-step explanation:

Polar form is in,

(r,theta).