Please help with this khan academy questions

ki77a [65]

Answer:

No

Step-by-step explanation:

17/10 is not proportional to 12/5. Proportional relationships are relationships between two variables where their ratios are equivalent. 17/10 as a ratio is 17:10 and 12/5 as a ratio would be 12:5. A proportional relationship for 12/5 would be 24/10.

Hope this helps :)

8 0

1 year ago

Read 2 more answers

Help please!!!!!!!!!

In-s [12.5K]

ANSWER

24

EXPLANATION

For a matrix A of order n×n, the cofactor $C_{ij}$ of element $a_{ij}$ is defined to be

$C_{ij} = (-1)^{i+j} M_{ij}$

$M_{ij}$ is the minor of element $a_{ij}$ equal to the determinant of the matrix we get by taking matrix A and deleting row i and column j.

Here, we have

$C_{11} = (-1)^{1+1} M_{11} = M_{11}$

M₁₁ is the determinant of the matrix that is matrix A with row 1 and column 1 removed. The bold entries are the row and the column we delete.

$\begin{aligned} A=\begin{bmatrix} \bf 1 & \bf -6 & \bf -4\\ \bf 7 & 0 & -3 \\ \bf -9 & 8 & -8 \end{bmatrix} \implies M_{11} &= \text{det}\left(\begin{bmatrix} 0&-3 \\ 8&-8 \end{bmatrix} \right) \end{aligned}$

Since the determinant of a 2×2 matrix is

$\det\left( \begin{bmatrix} a & b \\ c& d \end{bmatrix} \right) = ad-bc$

it follows that

$\begin{aligned} A=\begin{bmatrix} \bf 1 & \bf -6 & \bf -4\\ \bf 7 & 0 & -3 \\ \bf -9 & 8 & -8 \end{bmatrix} \implies M_{11} &= \text{det}\left(\begin{bmatrix} 0&-3 \\ 8&-8 \end{bmatrix} \right) \\ &= (0)(-8) - (-3)(8) \\ &= -(-24) \\ &= 24 \end{aligned}$

so $C_{11} = M_{11} = 24$

4 0

3 years ago

you are working as a Caterer and need 20 gallons of lemonade For an upcoming event. The bottles of lemonade you are purchasing a

kifflom [539]

20 imperial gallons = 90.9218 litres
so i'd say you'd need to buy 91 bottles or...

20 US Liquid gallons = 75.7082 litres
so you'd have to buy 76 bottles.
Hope this answers your question! It depends what gallon you're working from.

3 0

3 years ago

Read 2 more answers

Suppose you take an SRS of size 1000 of Connecticut students eligible to take the SAT and find that 85% plan to take the SAT dur

nadezda [96]

Answer:

$\mu_{p}=p=0.81$

Step-by-step explanation:

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".

The population proportion have the following distribution

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

So under the null hypothesis the mean for the population proportion is p

$\mu_{p}=p=0.81$

And the standard deviationis given by:

$\sigma_{p}=\sqrt{\frac{p_0(1-p_o)}{n}}=\sqrt{\frac{0.81(1-0.81)}{1000}}=0.0124$

7 0

3 years ago

Can someone help me with this

insens350 [35]

Let's solve this problem step-by-step.

STEP-BY-STEP EXPLANATION:

We will be using simultaneous equations to solve this problem.

The sum of angles on a straight line is 180°.

( R ) and ( 2x + 5 ) are both on the same straight line.

Therefore:

Equation No. 1 -

R + 2x + 5 = 180

R = 180 - 2x - 5

R = 175 - 2x

Vertically opposite angles are equivalent to each other.

( R ) is vertically opposite ( 3x + 15 ).

Therefore:

Equation No. 2 -

R = 3x + 15

Substitute the value of ( R ) from the first equation into the second equation to solve for ( x )

R = 3x + 15

175 - 2x = 3x + 15

- 2x - 3x = 15 - 175

- 5x = - 160

x = - 160 / - 5

x = 160 / 5

x = 32

Next we will substitute the value of ( x ) from the second equation into the first equation to solve for ( R ).

Equation No. 2 -

R = 175 - 2x

R = 175 - 2 ( 32 )

R = 175 - 64

R = 111

FINAL ANSWER:

Therefore, the answer is:

R = 111

x = 32

Hope this helps! :)
Have a lovely day! <3

7 0

3 years ago