Class A has 10 pupils and class B has 18 pupils. Both classes sit the same maths test. The mean score for class A is 34. The mean score for both classes is 55. What is the mean score (rounded to 2 DP) in the maths test for class B?

Answer:

x = -18, Y = -44

Step-by-step explanation:

Since Y = 2x - 8, we can substitute that into the first equation:

2x - 8 = 3x + 10

3x - 2x = -8 - 10

x = -18

Now we plug x = -18 back into the second equation:

Y = 2(-18) - 8

Y = -36 - 8

Y = -44

It should be noted that 16/25 can be converted to a terminating decimal number is 0.64.

Do the fractions 6/7 and 16/25 convert to repeating or terminating decimal numbers.

In this case, 6/7 converts to repeating decimal numbers. You could represent it, so you don't have to repeat the decimals infinitely, by putting a bar over the repeating decimals like 0.857142 with a bar going over from the 8 to the 2.

Also, 16/25 can be converted to a terminating decimal number which is 0.64.

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Answer:

QA) C = 31.4 cm, A = 78.5 cm^2

QB) 36 cm

Step-by-step explanation:

Question A

Circumference formula: 2πr

2π(5) = 31.4 cm

Area formula: πr^2

π(5)^2 = π(25) = 78.5 cm^2

Question B

If you extend the line of the shape to create a quadrilateral and a triangle, you can use the pythagorean theorem to figure out the last length.

9 - 6 = 3

10 - 6 = 4

The lengths of side a and b are 3 and 4, we need to find the length of the hypotenuse

a^2 + b^2 = c^2

3^2 + 4^2 = c^2

9 + 16 = c^2

25 = c^2

5 = c

Now we can combine this number with the rest of the given lengths

10 + 9 + 6 + 6 + 5 = 36 cm

Step-by-step explanation:

hope you can understand

Answer:

45

Step-by-step explanation:

When you're completing the square you're adding (b/2)^2 which in this case is (-5)^2 or 25. This is because when you rewrite it as a square binomial you write it in the form (x+(b/2))^2 which is going to result in x^2+b+(b/2)^2. Since you need to reach 25 you need to add 45 since the last value is at -20.

Answer:

25 to both sides

Step-by-step explanation:

Group x² and x terms

(x² - 10x ) - 20

complete the square

(x² - 10x +25 ) -20 -25

(x-5)² -45

Answer:

5.8

Step-by-step explanation:

Considering the discriminant of zero for a quadratic equation, the correct option is given by:

C. It has one real solutions.

A quadratic equation is modeled by:

[tex]y = ax^2 + bx + c[/tex]

The discriminant is:

[tex]\Delta = b^2 - 4ac[/tex]

The solutions are as follows:

Discriminant of zero is [tex]\Delta = 0[/tex], hence option C is correct.

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[tex]|\Omega|=6^2=36\\|A|=4\cdot3=12\\\\P(A)=\dfrac{12}{36}=\dfrac{1}{3}\approx33.3\%[/tex]

Answer: 1/5

Step-by-step explanation:

There are three kinds of Marbles. (M) marbles

(G) green: 4m

(R) red: 1m

(B) blue: 1m

Dan pulled a green marble out leaving

(G) green: 3m

So, the probability of picking a green marble is 1/5

sorry if I'm wrong/correct me if I'm wrong.

Answer:

x = 14.02 units

Step-by-step explanation:

Finding unknown value using Pythagorean theorem:

 This is an isosceles trapezium.  The two perpendiculars  divide the trapezium into two congruent triangles and a rectangle. Let the base of the triangle by 'y'. We can find the value of 'y' using Pythagorean theorem.      

In ΔABC,

                AC² = AB² + BC²

                   19² = 17 ² + y ²

                 361  = 289 + y ²

        361 - 289  = y ²

                      y ² = 72

                      y =√72

                      y = 8.49

x = 31 - 8.49 - 8.49

x = 14.02

The rotation about the origin that is equivalent to R-200° is; C. R160

We are given;

Origin = -200°

Now, even if we add and also subtract a complete rotation of 360° (or even several rotations of 360°), we will want to have the similar rotation.

Thus;

By adding 360° to -200°, we have;

α = -200° + 360°

α = 160°

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The green-colored area of the graph attached below shows the solution set to 3eˣ>(-1/2)x.

Inequality is the relationship between two expressions showing the relationships like greater than, lesser than, lesser than equals to, and greater than equals to.

Here assume f is a function which is given by f(x)=3eˣ

and g be another function which is given by g(x)= (-1/2)x

Here we have to find the solution graph showing the relationship

f(x) > g(x)

Let at point (a,b) the f(x) and g(x) meet each other.

After that intersection point, g(x) will decrease as g(x) is a decreasing function. and f(x) will increase.

So in the solution set will contain the area where g(x) is larger than f(x).

Therefore the solution graph of this inequality is the green-colored area as shown below,

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Answer:

58 cm

Step-by-step explanation:

if both shapes are squares, then the perimeter must be divide by all 4 equal sides

36 / 4 = 9, so each side of the first shape is 9 cm

40 / 4 =10 , so each side of the second shape is 10 cm

by putting the shapes together two of the side seal 1 side of each shape but 10-9 is 1 so add all three sides of the rest of the shape,

so 9+ 9+ 9= 27, then the three side of the second shape,

so 10+ 10+ 10= 30, then that extra 1 cm of difference from the size difference when put together,

so 27+ 30+ 1= 58 cm

The equation in slope-intercept form is y = 13/8x -17/8 and the equation in standard form is 13x -8y = 17

A line is the shortest distance between two points. The equation of a line in slope-intercept form is y = mx + b while as a standard notation is Ax+By = C

Given the coordinate points (-3, -7) and (5, 6)

Determine the slope

Slope = 6-(-7)/5-(-3)

Slope = 13/8

For the y-intercept

6 = 13/8(5) + b

6 = 65/8 + b

b = 6 - 65/8

b = -17/8

The equation in slope-intercept form is y = 13/8x -17/8

Write in standard form

Recall y = 13/8x - 17/8

Multiply through by 8

8y = 13x - 17

-13x + 8y = -17

13x -8y = 17

Hence the equation in standard form is 13x -8y = 17

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Answer:

the answer is A. 2 thin crust pizzas

Answer: 3
________________________________
initial value = starting value when x is 0

as you can see when x is 0 y is 3

so your initial value is 3

________________________________

Hoped this helped.

Answer:

m=-3

Step-by-step explanation:

Since the lines are parallel to each other, their gradients are equal.

∴ gradient of green line = gradient of red line

∴ m = -3

Solution: slope=-3

Detailed explanation:

This little problem asks us to find the slope of the line. Let's do this!

[tex]\searrow[/tex]

This is what parallel lines look like:

<------------------------------------------------------------------------------------------------------->

<------------------------------------------------------------------------------------------------------->

The two lines above will never intercept each other.

And that's what parallel lines are - they are lines that never intercept.

They can be vertical, horizontal, or diagonal, it doesn't matter. As long as both of them have the same slope and never intercept each other.

So, since parallel lines have identical slopes, the slope of the red line = slope of the green line (the problem provides us that both lines are parallel)

Slope of the red line = -3

Voila! There's our answer!

__________________________

Hope I helped! Best wishes!

Reach far. Aim high. Dream big.

"reflection"

__________________________

The range of shelter A is 22.  The range of shelter B is 18.

A box plot is used to study the distribution and level of a set of scores. The box plot consists of two lines and a box. the two lines are known as whiskers. The end of the first line represents the minimum number and the end of the second line represents the maximum number. The range is the difference between the two numbers.

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Answer:

x = 9

Step-by-step explanation:

-2x + 3 = -15

-2x = -18

x = 9

Answer:

Step-by-step explanation:

what value of x makes this equation true , use numerals instead of words.

-2x+3=-15

-2x + 3 = -15

-2x = -15 - 3

-2x = -18

x = -18 : (-2)

x = 9

--------------------

check

-2 * 9 + 3 = -15

-18 + 3 = -15

-15 = -15

the answer is good

Answer:

I think the answer is 5 ( if wrong then do a low rating)

Step-by-step explanation:

The way I found the answer was by using PEDMAS so first I handled [(4 - (-5)) x (-7)] which is the same as 4 + -5 which equals -1 and when multiplied by -7 equals positive 7 because whenever you multiply 2 negatives you get a positive.

Next I solved 6 / (-3) which is -2 since whenever a positive is divided by a negative the quotient is negative. Now the equation is:

-2 + 7 and when solved is -2 + 7 = 5

The value of a₃₂ is 7 , Option A is the correct answer.

Matrix is an array or an arrangement of numbers or expression in rows and column format.

The matrix is given

For a matrix of size mxn , m is the row and n is the column of the matrix.

a₃₂ = This term means 3rd row and 2nd column of the matrix

which is 7

Therefore the value of a₃₂ is 7 , Option A is the correct answer.

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Answer:

4

Step-by-step explanation:

DA²= CB×CA

6²= y×(y+5)

36=y²+5y

y²+5y-36=0

x1+x2=-5

x1×x2=36

x1=4

x2=-9

x must be positive, then answer is 4

chek: 4×9=36

If is -(-13/12) then A. -13/-12

If is -13/12 then B. 13/-12

[tex]-\dfrac{-13}{12}=\dfrac{-13}{-12}=\dfrac{13}{12}\\\\\dfrac{-13}{12}=-\dfrac{13}{12}=\dfrac{13}{-12}[/tex]

Answer:

D. n=3

Step-by-step explanation:

8-2n-6n= –16

Take 8 to the other side

-2n-6n= -16-8

Solve them

-8n = -24

Take -8 to the other side

[tex]n \: = \frac{ - 24}{ - 8} [/tex]

n = 3

[tex]\huge\text{Hey there!}[/tex]

[tex]\huge\textbf{Equation:}[/tex]

[tex]\mathbf{8 - 2n - 6n = -16}[/tex]

[tex]\huge\textbf{Solving for the answer:}[/tex]

[tex]\mathbf{8 - 2n - 6n = -16}[/tex]

[tex]\huge\textbf{Combine the like terms:}[/tex]

[tex]\mathbf{(-2n - 6n) + 8 = -16}[/tex]

[tex]\mathbf{-2n - 6n + 8 = -16}[/tex]

[tex]\mathbf{-8n + 8 = -16}[/tex]

[tex]\huge\textbf{Subtract \boxed{\bf 8} to both sides:}[/tex]

[tex]\mathbf{-8n + 8 - 8 = -16 - 8}[/tex]

[tex]\huge\textbf{Simplify it:}[/tex]

[tex]\mathbf{-8n = -16 - 8}[/tex]

[tex]\mathbf{-8n = -24}[/tex]

[tex]\huge\textbf{Divide \boxed{\bf -8} to both sides:}[/tex]

[tex]\mathbf{\dfrac{-8n}{-8} = \dfrac{-24}{-8}}[/tex]

[tex]\huge\textbf{Simplify it:}[/tex]

[tex]\mathbf{n = \dfrac{-24}{-8}}[/tex]

[tex]\mathbf{n = -24 \div -8}[/tex]

[tex]\mathbf{n = 3}[/tex]

[tex]\huge\textbf{Therefore, your answer should be:}[/tex]

[tex]\huge\boxed{\textsf{Option D. \boxed{\frak{n = 3}}}}\huge\checkmark[/tex]

[tex]\huge\text{Good luck on your assignment \& enjoy your day!}[/tex]

~[tex]\frak{Amphitrite1040:)}[/tex]

5) 2x + 8 - 4y - 1 = 2x - 4y + 7

6) -5x(3x² - 2x - 1) = -15x³ + 10x² + 5x

Answer:

option B, -(4x - 3)(x - 2)

Step-by-step explanation:

-4x^2 + 11x - 6

4x * x = 4x^2

x * -3x = -3x

-4x * -2 = -8x

-3 * -2 = -6

Probability helps us to know the chances of an event occurring. The estimated number of left-handed persons in the school is 89.

Probability helps us to know the chances of an event occurring.

[tex]\rm Probability=\dfrac{Desired\ Outcomes}{Total\ Number\ of\ outcomes\ possible}[/tex]

Given the number of girls is 320, the probability that a girl is left-handed is 0.2. Therefore, the number of girls who are left-handed is,

Number of left-handed girls = (320×0.2) = 64

Given the number of boys is 250, the probability that a boy is left-handed is 0.1. Therefore, the number of boys who are left-handed is,

Number of left-handed boys= (250×0.1) = 25

Hence, the estimated number of left-handed persons in the school is 89.

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Answer:

B. Arm circles

Hope you have a great day :)

The degree of freedom is 6.

The degrees of freedom for the chi-square are calculated using the following formula: df = (r-1)(c-1) where r is the number of rows and c is the number of columns.

Given:

rows= 3

column= 4

So, degree of freedom

= (row-1)(column-1)

=(3-1)(4-1)

=2*3

=6

Hence, the degree of freedom is 6.

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Answer:

The degree of freedom is 6.

Step-by-step explanation:

Got it right on the test.