Can someone pls help

Lisa [10]

Multiple 15 by 6, the answer is 90 square cm

7 0

3 years ago

A company surveyed 2400 men where 1248 of the men identified themselves as the primary grocery shopper in their household. a) E

polet [3.4K]

Answer:

a) With a confidence level of 98%, the percentage of all males who identify themselves as the primary grocery shopper are between 0.4962 and 0.5438.

b) The lower limit of the confidence interval is higher that 0.43, so if he conduct a hypothesis test, he will find that the data shows evidence to said that the fraction is higher than 43%.

c) $\alpha =1-0.98=0.02$

Step-by-step explanation:

If np' and n(1-p') are higher than 5, a confidence interval for the proportion is calculated as:

$p'-z_{\alpha/2}\sqrt{\frac{p'(1-p')}{n} }\leq p\leq p'+z_{\alpha/2}\sqrt{\frac{p'(1-p')}{n} }$

Where p' is the proportion of the sample, n is the size of the sample, p is the proportion of the population and $z_{\alpha/2}$ is the z-value that let a probability of $\alpha/2$ on the right tail.

Then, a 98% confidence interval for the percentage of all males who identify themselves as the primary grocery shopper can be calculated replacing p' by 0.52, n by 2400, $\alpha$ by 0.02 and $z_{\alpha/2}$ by 2.33

Where p' and $\alpha$ are calculated as:

$p' = \frac{1248}{2400}=0.52\\\alpha =1-0.98=0.02$

So, replacing the values we get:

$0.52-2.33\sqrt{\frac{0.52(1-0.52)}{2400} }\leq p\leq 0.52+2.33\sqrt{\frac{0.52(1-0.52)}{2400} }\\0.52-0.0238\leq p\leq 0.52+0.0238\\0.4962\leq p\leq 0.5438$

With a confidence level of 98%, the percentage of all males who identify themselves as the primary grocery shopper are between 0.4962 and 0.5438.

The lower limit of the confidence interval is higher that 0.43, so if he conduct a hypothesis test, he will find that the data shows evidence to said that the fraction is higher than 43%.

Finally, the level of significance is the probability to reject the null hypothesis given that the null hypothesis is true. It is also the complement of the level of confidence. So, if we create a 98% confidence interval, the level of confidence $1-\alpha$ is equal to 98%

It means the the level of significance $\alpha$ is:

$\alpha =1-0.98=0.02$

4 0

3 years ago

One number exceeds another by 2 the sum of the number is 48 what are the numbers

Bond [772]

$x-\ first\ number\\y-\ second\ number\\\\
 \left \{ {{x-y=2} \atop {x+y=48}} \right. \\\\ \left \{ {{x=2+y} \atop {x+y=48}} \right. \\\\Substution\ method\\\\
2+y+y=48\\\\
2+2y=48\\\\
2y=46\ \ \ |:2\\\\
\boxed{y=23}$

3 0

3 years ago

On a coordinate grid, point A is located in the first quadrant. Point B is located at (2, - 1/2

Nookie1986 [14]

Answer:

It's where point B is at (2,0.5)

8 0

2 years ago

There are 100 tiles in a word game, and 2 of the tiles are blank. Kiera draws 6 tiles, and none of them are blank.

Kay [80]

Answer:

$\frac{1}{47}$ or around 2%

Step-by-step explanation:

So we need to see how many tiles are left.

100 - 6 = 94

So we have 94 tiles. 2 of them are blank, so the chance of one being blank is:

2 / 94 which is $\frac{1}{47}$

And that is our answer! Hopefully this helps, have a nice day :D

7 0

3 years ago