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3 years ago

I’m not understanding the answer listed on this site to the following question:

1 answer:

4 0

Okay, I think I understand this. Our first step is to solve how long the string is after he used some of it to tie the package. I have a feeling we have to subtract 7/8 - 1/5. Find a least common multiple (in this case, it's 40) and our new fractions are 35/40 and 8/45. Subtract:

35/40 - 8/40 = 27/40.

I don't think this can be simplified down any further as they do not have any common factors. So with that in mind, let's divide 27/40 with 5/1 (5/1 is basically 5 wholes but in fraction version)

When dividing fractions, you want to use the KCF technique (my old math teacher taught me this). Keep the first fraction the same (in this case, 27/40), change the sign from multiplication to division, and flip 5/1 to get it's reciprocal, 1/5. The equation will look like this:

27/40 * 1/5 = 27/200

So each piece is about 27/200 m in length (or 0.135 m in length).

If this is wrong, please let me know, but this is what I got out of this question. I hope this helped you :)

You might be interested in

Find the measure of the numbered angle.

Mila [183]

The angle adjacent to angle 6 is the one we need to find first. To do this, add the measures of the intercepted arcs and divide by 2. 60 + 50 = 110, and half of that is 55. That means that both adjacent angles to the angle 6 are 55 (vertical angles are congruent). The measure of all the angles added together is 360 and angle 6 is vertical to the other "sideways" angle, so they are congruent as well. 360 - 55 - 55 = 250. Split that up between angle 6 and its vertical angle to get that each of those measure 125. Angle 6 measures 125, choice b from above.

4 0

3 years ago

Find the greatest common factor 7x^3a+7x^2a^2

muminat

Answer:

7x^2a

Step-by-step explanation:

7x^3a+7x^2a^2

7x^3a = 7 xxxa

7x^2a^2= 7 xxaa

The common terms are 7xxa

7x^2a

This is the greatest common factor

6 0

3 years ago

6÷2(1+2)= _____ whats the answer to this

GalinKa [24]

Answer:

Step-by-step explanation:

You do parenthesis first so 1+2=3

Then you do division 6 divided by 2=3

Then you will multiply 3 by 3 so 9

This is known as pemdas

P=parenthesis

E=exponents

MD=multiplication and division you do it left to right so if division is in front of multiplication then you do division

As=Addition and subtraction is also left to right

8 0

2 years ago

Read 2 more answers

Which number between 20 and 28 are prime

ad-work [718]

Prime numbers basically numbers that dont have any numbers that will be multiplied to get to it. So, it would be:
23
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
All the other numbers in between can be divided by something and not become a decimal. Other than 23, it can be divided by anything without becoming a decimal.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~Hope this helped :)

4 0

4 years ago

Read 2 more answers

A survey reported in Time magazine included the question ‘‘Do you favor a federal law requiring a day waiting period to purchase

il63 [147K]

Answer:

The 90% confidence interval for the difference between proportions is (-0.260, -0.165).

Step-by-step explanation:

The question is incomplete. The complete question is:

"A survey reported in Time magazine included the question ‘‘Do you favor a federal law requiring a 15 day waiting period to purchase a gun?” Results from a random sample of US citizens showed that 318 of the 520 men who were surveyed supported this proposed law while 379 of the 460 women sampled said ‘‘yes”. Use this information to find a 90% confidence interval for the difference in the two proportions, pm - pw. Subscript pm is the proportion of men who support the proposed law and pw is the proportion of women who support the proposed law. (Round answers to 3 decimal places.)"

We want to calculate the bounds of a 90% confidence interval.

For a 90% CI, the critical value for z is z=1.645.

The sample of men, of size nm=-0.26 has a proportion of pm=0.612.

$p_m=X_m/n_m=318/520=0.612$

The sample 2, of size nw= has a proportion of pw=0.824.

$p_w=X_w/n_w=379/460=0.824$

The difference between proportions is (pm-pw)=-0.212.

$p_d=p_m-p_w=0.612-0.824=-0.212$

The pooled proportion, needed to calculate the standard error, is:

$p=\dfrac{X_m+X_w}{n_m+n_w}=\dfrac{318+379}{520+460}=\dfrac{697}{980}=0.711$

The estimated standard error of the difference between means is computed using the formula:

$s_{pm-pw}=\sqrt{\dfrac{p(1-p)}{n_m}+\dfrac{p(1-p)}{n_w}}=\sqrt{\dfrac{0.711*0.289}{520}+\dfrac{0.711*0.289}{460}}\\\\\\s_{pm-pw}=\sqrt{0.00039+0.00045}=\sqrt{0.001}=0.029$

Then, the margin of error is:

$MOE=z \cdot s_{pm-pw}=1.645\cdot 0.029=0.0477$

Then, the lower and upper bounds of the confidence interval are:

$LL=(p_1-p_2)-z\cdot s_{p1-p2} = -0.212-0.0477=-0.260\\\\UL=(p_1-p_2)+z\cdot s_{p1-p2}= -0.212+0.0477=-0.165$

The 90% confidence interval for the difference between proportions is (-0.260, -0.165).

6 0

3 years ago