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3 years ago

Review the scenario and the solution. Explain what is wrong with solution and correct the error.

Mathematics

2 answers:

butalik [34]3 years ago

7 0

2.25h(60m/hr)(1/3)=45m

So Rick spends 45 minutes studying math per night.

andrezito [222]3 years ago

5 0

He spends 45 minutes doing math.

Work - 2.25 time 60 gives the number of minutes he spent total = 135.
135 divided by 3 give the amount of time he worked on math since he
spent a third of his time on math.

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By rounding to 1 significant figure, estimate<br> 22.4 x 49.8

seropon [69]

Answer is 1115,5
here is how

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3 years ago

Read 2 more answers

The expression below is the factorization of what trinomial-1(x+5)(x+6)

Nadya [2.5K]

Answer:

-x^2 - 11x -30

Step-by-step explanation:

Solve using foiling. Ignore the -1 to begin with and just look at the part in parenthesis. Do x from the first parenthesis times the stuff in the second parenthesis.

ie: x(x) and x(6)

ie: x^2 + 6x

Then do the 5 times the things in the second parenthesis.

ie: 5(x) and 5(6)

ie: 5x + 30

Then add what you got from multiplying the first value to what you got from multiplying the second.

ie: x^2 + 11x + 30

This is a trinomial because it has three different variables. Now change all the signs to negative because of the -1 out front.

ie: -x^2 - 11x -30

4 0

3 years ago

Geneva's younger brother has a toy box that is 3.6 feet

Anestetic [448]

Answer:

12.96 ft ³

Step-by-step explanation:

3 0

3 years ago

I neeeed help realy bad

77julia77 [94]

Answer: -3x + 4, (2,-2)

Step-by-step explanation:

First, you want to get y alone on one side.

3x + y = 4

-4 -4 subtract 4 to get it on the left side.

-y -y subtract y to get it alone on the right side.

Your'e left with 3x - 4 = -y divide the whole equation by -1 do get a pos y

You then have y = -3x + 4. That's the first part of your answer.

To get the second part plug in (-3x + 4) into the y of the first equation, this is the substitution part.

-2x + 5(-3x+4) =-14 distribute the 5... -2x - 15x +20 = -14

add your like terms ( x and x) -17x + 20 = -14

Isolate your x by subtracting the 20, both sides -20 -20

-17x = -34 divide both side by 17 you get x = 2 (---- this is your first coordinate in the pair in your answer. To get the y do the same but solve for y instead of x.

3 0

3 years ago

Tain has a great literary tradition that spans centuries. One might assume, then, that Britons read more than citizens of other

tresset_1 [31]

Answer:

Null hypothesis: $p_{1} \leq p_{2}$

Alternative hypothesis: $p_{1} > p_{2}$

$z=3.02$

$p_v =P(Z>3.02)=0.00127$

The p value is a very low value and using any significance level for example $\alpha=0.05, 0,1,0.15$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say the the proportion of Canadians is not significantly higher than the porportions of readers at Britons.

Step-by-step explanation:

1) Data given and notation

$X_{1}=0.86*1004$ represent the number of Canadians randomly sampled by Gallup that read at least one book in the past year

$X_{2}=0.81*1009$ represent the number of Britons randomly sampled that read at least one book in the past year

$n_{1}=1004$ sample of Gallup selected

$n_{2}=1009$ sample of Britons selected

$p_{1}=0.86$ represent the proportion of Canadians randomly sampled by Gallup that read at least one book in the past year

$p_{2}=0.81$ represent the proportion of Britons randomly sampled that read at least one book in the past year

z would represent the statistic (variable of interest)

$p_v$ represent the value for the test (variable of interest)

2) Concepts and formulas to use

We need to conduct a hypothesis in order to check if the proportion for men with red/green color blindness is a higher than the rate for women , the system of hypothesis would be:

Null hypothesis: $p_{1} \leq p_{2}$

Alternative hypothesis: $p_{1} > p_{2}$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{0.81+0.86}{2}=0.835$

3) Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.86-0.81}{\sqrt{0.835(1-0.835)(\frac{1}{1004}+\frac{1}{1009})}}=3.02$

4) Statistical decision

For this case we don't have a significance level provided $\alpha$ , but we can calculate the p value for this test.

Since is a one side test the p value would be:

$p_v =P(Z>3.02)=0.00127$

So the p value is a very low value and using any significance level for example $\alpha=0.05, 0,1,0.15$ always $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say the the proportion of Canadians is not significantly higher than the porportions of readers at Britons.

5 0

3 years ago