Một lớp có 40 học sinh gồm học sinh giỏi, học sinh khá , và học sinh trung bình , số hs trung bình chiếm 1/4 cả lớp , số hs khá bằng 60% số học sinh còn lại a) tính số học sinh mỗi loại B) tổng số hs khá và giỏi chiếm bao nhiêu phần trăm trong lớp

Answer:

Step-by-step explanation:

The diagonal must be an angle bisector for a rhombus.

That means that both bisected angles are equal.

2x + 16 = 5x - 8            Add 8 to both sides

2x + 16 + 8 = 5x

2x + 24 = 5x                 Subtract 2x from both sides

24 = 5x - 2x

24 = 3x                         Divide by 3

24/3 = x

x = 8

Answer:

C= 40

D= 75

Alternate interior angle

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Hope it helps...

Have a great day!!!

Answer:

80/3

Step-by-step explanation:

try mathw4y it helps alot.

Answer:

x = 80/3

Step-by-step explanation:

(4x+38) + (2x-18)=180

Combine like terms

6x +20 = 180

Subtract 20 from each side

6x+20 -20 = 180-20

6x = 160

Divide by 6

6x/6 = 160/6

x = 80/3

Answer:

+6

Step-by-step explanation:Look at the trend of numbers and notice. Maybe put it in a table.

Answer:

[tex] \displaystyle a = \frac{1+vh}{v}[/tex]

Step-by-step explanation:

we want to figure out a value of a for the following condition

[tex] \displaystyle va - vh = 1[/tex]

to do so factor out v;

[tex] \displaystyle v (a - h )= 1[/tex]

divide both sides by v which yields:

[tex] \displaystyle \frac{(a-h) \cancel{(v)}}{ \cancel{v}}= \frac{1}{v} [/tex]

therefore,

[tex] \displaystyle a-h = { \frac{1}{v}}[/tex]

now,add h to both sides:

[tex] \displaystyle a = \frac{1}{v}+h[/tex]

further simplification if necessary:

[tex] \displaystyle a =\boxed{ \frac{1+vh}{v}}[/tex]

factor out of v

Dividing both sides by (v)

cancel out (v)

add h in both sides

cancelout h

[tex]\sf{ }[/tex] [tex]\sf{ }[/tex]

the value of a if va- vh is equals to 1 is [tex]\bold{\dfrac{1+vh}{v} }[/tex]

Answer:

D. Ana is 3 years older than Mark.

Step-by-step explanation:

We do not know how old Mark is.  That is the variable

Answer:

Step-by-step explanation:

adjacent angles have a common vertex and a common ray

∠BEC and ∠AEB (common vertex E common ray EB)

Answer:

7^-22

Step-by-step explanation:

Exponent laws.

Answer:

Answer

Step-by-step explanation:

please like and mark me brainlist

Answer:

Relative error = 0.19

Step-by-step explanation:

From the question given above, the following data were obtained:

Measured age = 32 years

Actual age = 27 years

Relative error =?

Next, we shall determine the absolute error. This can be obtained as follow:

Measured age = 32 years

Actual age = 27 years

Absolute error =?

Absolute error = | Measured – Actual |

Absolute error = | 32 – 27 |

Absolute error = 5 years

Finally, we shall determine the relative error. This can be obtained as follow:

Absolute error = 5 years

Actual age = 27 years

Relative error =?

Relative error = Absolute error / Actual years

Relative error = 5 / 27

Relative error = 0.19

Answer:

I'm sorry I'm not good at math

Step-by-step explanation:

sorry

[tex]\sf \: If \: the \: question \: is \: to \: convert \: - 0.6 \\ \sf \: to \: its\: equivalent \: fractional \: form \: then ⟹[/tex]

[tex]\sf \: - 0.6 \\ \sf= \frac{ - 6}{10} (direct \: fractional \: form) \\ \sf = \frac{ - 3}{5} (in \: simplified \: form)[/tex]

Answer:

732 m^2

Step-by-step explanation:

Find the area of the full rectangle

33*24 =792

Find the area of the triangle

24-16 = 8

33 -18 =15

The area of the triangle is

A = 1/2 bh = 1/2 ( 15)(8) = 60

Subtract the triangle from the rectangle

792 - 70=732 m^2

Answer:

732 [tex]m^2[/tex]

Step-by-step explanation:

First we can find the area of the shape if the triangle wasn't there. That would be:

24×33=792.

Then, we can find the area of the triangle to subtract that from the total.

The formula for the area of a triangle is [tex]A=\frac{1}{2} bh[/tex].

So [tex]A=\frac{1}{2} (8)(15)[/tex]

I found the base of the triangle by subtracting 16 from 24.

I found the height of the triangle by subtracting 18 from 33.

Now, solve the equation.

[tex]A=\frac{1}{2}( 120)[/tex]

A=60

Then finally, Subtract 60 from 792.

You get 732.

I hope this helps!

Answer:

Sa / Va = time traveled by bus a

Sb  / Vb + 3/4  = time traveled by van b

Sa / Va = Sb  / Vb + 3/4      times traveled are the same

            = (220 - Sa) / Vb + 3/4

Sa ( 1 / Va + 1 / Vb) = 220 / 80 + 3/4

Sa (140 / 4800) = 3.5

Sa = 120 km

Check: 120 km / 60 km/hr = 2 hr = Ta

Sb = 1.25 * 80 = 100 km   traveling for 1.25 hrs

Answer:

41/10

Explanation:

sqrt16 = 4

sqrt17 = 4.12

4.1 = 41/10 and 4<4.1<4.12

Answer:

simple 49+44=93 then you do 180 is the angle of a straight line so we do 180-93=87

Using the Pythagorean theorem:

Hypotenuse = sqrt( 20^2 + 15^2)

Hypotenuse = sqrt( 400 + 225)

Hypotenuse = sqrt(625)

Hypotenuse = 25

Answer: 25 inches

Answer:

25 inches

Step-by-step explanation:

We can use the Pythagorean theorem

a^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse

20^2 + 15^2 = c^2

400 +225 = c^2

625=c^2

Taking the square root of each side

sqrt(625) = sqrt(c^2)

25 = c

Answer:

Step-by-step explanation:

If we divide 24 by 6, we get 4, which is the other factor of 24 when given the one factor of 6. Same goes here. In order to find out what the other factor of [tex]y^2-10y+24=0[/tex] is when given one factor of y - 4, we simply divide the second degree polynomial by y - 4 to get the quotient. The quotient, then, is the other factor. Synthetic division is the easiest way to do this.

If y - 4 is the factor, then by the Zero Product Property, y - 4 = 0 and y = 4. Setting up synthetic division:

4|   1    -10     24

____________

The rule is to start by bringing down the first term, multiplying it by the number outside, then putting that product up under the next term in line:

4|   1     -10     24

             4          

     1

Then add the column, multiply the sum by the number outside, and put that product up under the next term in line:

4|    1     -10     24

               4    -24

      1      -6

And add the last column and that is the remainder. We get a 0 remainder. That means that y - 4 goes evenly into the polynomial and the other factor we are looking for is found in the numbers under the addition line. These numbers are the leading coefficients of the depressed polynomial, the polynomial that serves as the other factor: 1y - 6.

Therefore, the 2 factors that multiply together to give us [tex]y^2-10y+24=0[/tex] are (y - 4)(y - 6) and we can check ourselves by multiplying this out by FOILing to see if the result is the polynomial we started with. It is, so we're all done!

Answer:

its ( y-6 )

Step-by-step explanation:

well if you use the FOIL method you will get that answer. also i took the test and got a 100 so there u go.

Step-by-step explanation:

The depth of the water is increasing by 2 feet each minute.

Answer:

1/6 is less than 1/2

Step-by-step explanation:

1/6 is close to 0

8/9 is close to 1

1/6 is less than 1/2

=============================================================

Explanation:

10% in decimal form is 0.10

25% in decimal form is 0.25

The jump from 0.10 to 0.25 is "times 2.5" since (0.25)/(0.10) = 2.5

This means that we have 2.5 times as many apples compared to oranges.

If we have 2 oranges, as mentioned in every answer choice, then we must have 2*2.5 = 5 apples.

Based on this, the answer is either A or B.

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

65% turns into 0.65

The jump from 0.10 to 0.65 is 6.5 since (0.65)/(0.10) = 6.5

So we have 6.5 times as many pears as oranges.

If we had 2 oranges, then we have 2*6.5 = 13 pears

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

To summarize, we have:

2 oranges, 5 apples, 13 pears.

The answer is therefore choice A

Answer:

$0.25

Step-by-step explanation:

We can use System of Equations to find out how much a can of cat food costs.

Let's use variables to represent the cat food and dog food:

x = cost of 1 cat food can

y = cost of 1 dog food can

Here are our 2 equations based on the scenarios in the question:

4x + 3y = 1.99

4x + y = 1.33

Now let's set the second equation to y using basic algebra:

4x + y = 1.33

y = -4x+1.33

And we're going to plug that value of y, which is -4x+1.33 into the first equation and solve:

4x + 3y = 1.99

4x + 3(-4x+1.33) = 1.99

4x + -12x+3.99 = 1.99

-8x + 3.99 = 1.99

-8x = -2

x = 1/4

x = 0.25

1 can of cat food costs $0.25

Hope that helps (●'◡'●)

Answer:

.25

Step-by-step explanation:

set up equations

1)4c+3d=1.99

2)4c+d=1.33

Method of use:Elimination

          4c+3d=1.99

       - (4c+d)=-(1.33)

        ___________

=2d=.66

divide by two on both sides to get .33 for d.

plug in

4c+.33=1.33

subtract .33 on both sides

4c=1

divide by four on both sides to get c

c=1/4 or .25

Answer: A and C

Step-by-step explanation:

Answer:

4

Step-by-step explanation:

Length of the y component is how far the vector reaches vertically, so in this case it's 4

Answer:

[tex]162.07[/tex]

Step-by-step explanation:

An image that creates represents this situation has been attached to this answer. As one can see, the diagram models the situation, the angle of depression represents the angle between the horizon line and the line of sight. The horizon line and the tower form a right angle (a (90) degree angle). This means that the angle of depression is complementary to the angle of sight. Therefore, one can state the following:

[tex](angle\ of\ depression) + (angle\ of \ sight)=90[/tex]

Substitute,

[tex](angle\ of\ depression) + (angle\ of \ sight)=90[/tex]

[tex](m<ABD)+(m<DBC)=90[/tex]

[tex]42+(m<DBC)=90[/tex]

Inverse operations,

[tex]42+(m<DBC)=90[/tex]

[tex]m<DBC=48[/tex]

Now one can use the right angle trigonometric ratios to solve this problem. The right angle trigonometric ratios are a series of ratios that describe the relationship between the sides and angles in a right triangle. These ratios are as follows:

[tex]sin(\theta)=\frac{opposite}{hypotenuse}\\\\cos(\theta)=\frac{adjacent}{hypotenuse}\\\\tan(\theta)=\frac{opposite}{adjacent}[/tex]

Bear in mind, the terms (opposite) and (adjacent) are subjective, and change depending on the reference angle. However, the term (hypotenuse) refers to the side opposite the right angle and is constant regardless of the reference angle.

In this case, one has found an angle in the triangle, one is given the measure of the side opposite this angle, and one is asked to find the side adjacent to this angle. Therefore, it would make the most sense to use the ratio tangent (tan).

[tex]tan(\theta)=\frac{opposite}{adjacnet}[/tex]

Substitute,

[tex]tan(48)=\frac{180}{adjacent}[/tex]

Inverse operations,

[tex]tan(48)=\frac{180}{adjacent}[/tex]

[tex]adjacent=\frac{180}{tan(48)}[/tex]

[tex]adjacent=162.07[/tex]

Answer:

x = 29.5

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

cos x = adj side/ hypotenuse

cos x = 67/77

Taking the inverse cos of each side

cos^-1( cos x) = cos^-1 (67/77)

x = 29.52626525

To the nearest tenth

x = 29.5

4/6

Mr. williams wants to buy 4/6

Answer:

there is some missing information  here

if the pas is a dozen brownies

1/2 of a pan is 6 2/3 of 6 would be "4"

how much mac-n-cheese are being made?

that information would be needed to solve this

Step-by-step explanation:

Answer:

$7 is his Hourly Wage.

Step-by-step explanation:

We can start by finding out how much money Jada started with by adding the amount of money he had after buying the cake with how much he spent on the cake, 86 + 12 = 98.

We now know how much money he had before buying anything. Now we can just divide the total amount of money by how long he worked.

98 ÷ 14 = 7

Answer:

Hello,

Step-by-step explanation:

All i can do is to show you the ellipse.