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andriy [413]
3 years ago
10

No need of a answer anymore.

Mathematics
1 answer:
Rom4ik [11]3 years ago
5 0

Answer:

mean score of class B = 1778/25 = 71.12

Step-by-step explanation:

This was your question : Class A has 12 pupils and class B has 25 pupils. Both classes sit the same maths test. The mean score for class A is 80. The mean score for both classes is 74. What is the mean score (rounded to 2 DP) in the maths test for class B?

mean of class A = Σfx/Σf

mean of class A =  80

Σfx = 80 × 12 = 960

Mean score for both classes = 74

where

b = Σfx  of class B

960 + b/37 = 74

cross multiply

960 + b = 2738

b = 2738 - 960

b = 1778

mean score of class B = Σfx/Σf

Σfx = 1778

Σf = 25

Therefore,

1778/25 = 71.12

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Evgesh-ka [11]

Answer:Null hypothesis:  

Alternative hypothesis:  

 

 

The p value obtained was a very high value and using the significance level given  we have  so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of orders that were not accurate is not significant different from 0.1 or 10% .  

and the accuracy of the test yes is acceptable since the p value obtained is large enough to fail to reject the null hypothesis

Step-by-step explanation:

Data given and notation n  

n=367 represent the random sample taken

X=32 represent the orders that were not accurate

estimated proportion of orders that were not accurate

is the value that we want to test

represent the significance level

Confidence=95% or 0.95

z would represent the statistic (variable of interest)

 

Alternative hypothesis:  

When we conduct a proportion test we need to use the z statisitc, and the is given by:  

(1)  

The One-Sample Proportion Test is used to assess whether a population proportion  is significantly different from a hypothesized value .

Calculate the statistic  

Since we have all the info requires we can replace in formula (1) like this:  

 

Statistical decision  

It's important to refresh the p value method or p value approach . "This methos is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.  

The significance level provided . The next step would be calculate the p value for this test.  

Since is a bilateral test the p value would be:  

 

So the p value obtained was a very high value and using the significance level given  we have  so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 5% of significance the proportion of orders that were not accurate is not significant different from 0.1 or 10% .  

3 0
3 years ago
The parent function f(x)=x^2 is translated such that the function g(x)=-x^2+6x-5 represented the new function. What is true abou
Alla [95]
<h3>Answer:</h3>
  • g(x) has an axis of symmetry at x = 3
  • g(x) is shifted right 3 units from the graph of f(x)
  • g(x) is shifted up 4 units from the graph of f(x)
<h3>Step-by-step explanation:</h3>

The vertex form of g(x) is ...

... g(x) = -(x -3)² +4

This is offset to the right by 3 and up by 4 from the parent function. (It is also first reflected across the x-axis.)

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<em>Vertex form</em>

You know the leading coefficient is -1 because that's what it is for x² in the given form. When you factor -1 from the first two terms, of the given form, you have ...

... g(x) = -1(x² -6x) -5

Half the x coefficient inside parentheses will be the constant in the squared binomial term, so that term is (x -3)². The constant in that square is +9, so adding that value inside and outside parentheses in g(x) gives ...

... g(x) = -1(x² -6x +9) -5 +9

... g(x) = -(x -3)² +4 . . . . . vertex form

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<em>About transformations</em>

g(x) = f(x -a) causes the graph of f(x) to be shifted "a" units to the right. For a function f(x) with an axis of symmetry at x=0, it moves the axis of symmetry to x=a.

g(x) = f(x) +a causes the graph of f(x) to be shifted "a" units up.

g(x) = -f(x) causes the graph of f(x) to be reflected across the x-axis.

Here, we have all three of these transformations. First is the reflection:

... f₁(x) = -f(x) = -x²

Then we have shifting to the right 3 units. (also moves the axis of symmetry)

... f₂(x) = f₁(x-3) = -(x -3)²

Finally, we have shifting up 4 units.

... g(x) = f₂(x) +4 = -(x -3)² +4

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Answer:

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Step-by-step explanation:

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You are saving money for a summer camp that cost $1800. You have saved $500 so far, and you have 14 more weeks to save the total
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Answer: $92. 86, or rounded to the neared dollar $93.00 a week.

Step-by-step explanation:

The first thing you must do when solving math word probelms is to read it carfully, then take out all the number and say what they all stand for:

1800 = the amount of money you need.

500 = the amount of money you have.

14 = how many weeks you have left.

Now that you have your numbers layed out we must for the equation:

So we know that you have 500 dollars right now:

500

And let’s say x is how many weeks you have left:

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We also know that the sum of those two numbers are equal to the amount of money that you need:

500 + 14x = 1800

Now that we have the equation, we must solve it:

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Subtract the 500( the money we have) with 1800( the money we need):

14x = 1300

Now we must divide 14 by 1300:

x = 92. 86

We now have you answer: you must make $92. 86 each week to be able to go to your camp.

Hope this helps! :)

6 0
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