All categories

3 years ago

How can the commutative property be used to write multiplication sentences

1 answer:

4 0

Using the commutative property means that you could do 5x4=20 and flip it around so it’s 4X5 the answer would still be 20 but in a different order

You might be interested in

In a rectangle KLMN, the diagonals KM and LN intersect at O.

elena-s [515]

Answer:

8y°±94°⊂⊂100°

Step-by-step explanation:

7 0

3 years ago

5 1/3 * (-3 9/18) Simplify and Show your work

ANEK [815]

5/3*-3*9/18
5*-9/18
-45/18
-2.5

5 0

2 years ago

Given A = {(1, 3)(-1, 5)(6, 4)}, B = {(2, 0)(4, 6)(-4, 5)(0, 0)} and C = {(1, 1)(0, 2)(0, 3)(0, 4)(-3, 5)}, answer the following

ANEK [815]

$B=\{(\boxed{2}\ 0);\ (\boxed{4},\ 6);\ (\boxed{-4},\ 5);\ (\boxed{0},\ 0)\}\\\\(x,\ y)-domain\ is\ "x"\\\\Answer:\ 2.\ Domain\ of\ set\ B:\{2,\ 4,\ -4,\ 0\}$

8 0

2 years ago

Use the normal distribution to find a confidence interval for a difference in proportions p1-p2 given the relevant sample result

9966 [12]

Answer:

a) $\hat p_1 -\hat p_2= 0.2-0.35= -0.15$

b) $ME= 2.58 \sqrt{\frac{0.2(1-0.2)}{60} +\frac{0.8(1-0.8)}{100}} =0.169$

c) $(0.2-0.35) - 2.58 \sqrt{\frac{0.2(1-0.2)}{60} +\frac{0.8(1-0.8)}{100}} =-0.319$

$(0.2-0.35) + 2.58 \sqrt{\frac{0.2(1-0.2)}{60} +\frac{0.8(1-0.8)}{100}} =0.0185$

And the 99% confidence interval would be given (-0.319;0.0185).

Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

The margin of error is the range of values below and above the sample statistic in a confidence interval.

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".

$p_1$ represent the real population proportion 1

$\hat p_1=0.2$ represent the estimated proportion 1

$n_1=60$ is the sample size required 1

$p_2$ represent the real population proportion for 2

$\hat p_2 =0.35$ represent the estimated proportion 2

$n_2=100$ is the sample size required for Brand B

$z$ represent the critical value for the margin of error

Solution to the problem

The population proportion have the following distribution

$p \sim N(p,\sqrt{\frac{p(1-p)}{n}})$

The confidence interval for the difference of two proportions would be given by this formula

$(\hat p_1 -\hat p_2) \pm z_{\alpha/2} \sqrt{\frac{\hat p_1(1-\hat p_2)}{n_1} +\frac{\hat p_2 (1-\hat p_2)}{n_2}}$

Part a

The best estimate is given by:

$\hat p_1 -\hat p_2= 0.2-0.35= -0.15$

Part b

For the 99% confidence interval the value of $\alpha=1-0.99=0.01$ and $\alpha/2=0.005$ , with that value we can find the quantile required for the interval in the normal standard distribution.

$z_{\alpha/2}=2.58$

The margin of error is given by:

$ME= 2.58 \sqrt{\frac{0.2(1-0.2)}{60} +\frac{0.8(1-0.8)}{100}} =0.169$

Part c

And replacing into the confidence interval formula we got:

$(0.2-0.35) - 2.58 \sqrt{\frac{0.2(1-0.2)}{60} +\frac{0.8(1-0.8)}{100}} =-0.319$

$(0.2-0.35) + 2.58 \sqrt{\frac{0.2(1-0.2)}{60} +\frac{0.8(1-0.8)}{100}} =0.0185$

And the 99% confidence interval would be given (-0.319;0.0185).

4 0

3 years ago

Jenna uses 512 foot of yellow ribbon and 212 foot of red ribbon to make a bookmark for her sister. Which expression is equivalen

Ostrovityanka [42]

Seeing as they’re asking us only the total amount of ribbon (not the amount of just red or just yellow ribbon), all we have to do is add these two together.

512+212 = 724, so she used 724ft of ribbon in total (red + yellow). (I really don’t know why she would need that much, but hey, that’s her business, I guess :) )

5 0

2 years ago