In a test, +3 marks are given for every correct answer and -1 mark are given for every incorrect answer. Sona attempted all the questions and scored +20 marks, though she got 10 correct answers. How many incorrect answers has she attempted? (ii) How many questions were given in the test?

Answer:

cot(x)=-sqrt(3)/3

Step-by-step explanation:

I'm going to use the Pythagorean Identity sin^2(x)+cos^2(x)=1 to find the sine value since cotangent value is the cosine value over sine value.

Plug in:

sin^2(x)+(-1/2)^2=1

Simplify:

sin^2(x)+1/4=1

Subtract 1/4 on both sidea:

sin^2(x)=3/4

Square root both sides:

sin(x)=sqrt(3)/2. [Sine is positive since x is in 2nd quadrant]

cot(x)=(-1/2)/(sqrt(3)/2))

cot(x)=-1/sqrt(3)

Rationalize denominator by multiplying by sqrt(3)/sqrt(3):

cot(x)=-sqrt(3)/3

cot(x)=

Answer:

x = 10

Step-by-step explanation:

[tex]x^2 = 8^2 + 6^2\\x^2 = 64 + 36 = 100\\x = \sqrt{100} = 10[/tex]

Answer:

11/16

Step-by-step explanation:

9+2+5=16

9+2=11

11/16

Answer:

You use ratios to determine, so to find blue crayons it will be 16/2 chance of finding a blue crayon since there are 16 crayons and 2 blue crayons, and simplified it will be 8/1, you can find out the red crayon also by doing the same thing, since you are trying to get a red or blue crayon it will be 11/16 chance of finding a blue or red crayon.

Answer:

It would cost $21.30 for Robert to buy 6 notebooks.

Step-by-step explanation:

find cost for each notebook:

28.40 ÷ 8 = 3.55

multiply by 6:

3.55 x 6 = 21.3

Hope this helped!

Answer:

[tex] {x}^{0} y + 9 \\ = y + 9[/tex]

Answer:

4f + 3g

Step-by-step explanation:

g + 3f + f + g + g

3f + f = 4f

g + g = 2g + g = 3g

4f + 3g

Answer:

Of is a keyword for multiplication.

So, your equation is really 2 X 1,800,000÷3=?

Final answer: 1,200,000

Step-by-step explanation:

Hope that this helps! :)

Have a great rest of your day/night!

Answer:

3.25"

Step-by-step explanation:

If the scale is 1/8, then the model or drawing has lengths which are 1/8 of the objects lengths.

Find 1/8 of 26.

[tex]26 \times \frac{1}{8} = \frac{26}{8}= 3.25[/tex]

Answer:

a = -2

Step-by-step explanation:

Given that,

-1 is a zero of the polynomial. i.e. x = -1.

The polynomial is :

p(x) = ax²-x²+x+4

We need to find the value of a.

Put x = -1 in the above polynomial.

p(1) = a(-1)²-(-1)²+(-1)+4

For zeroes,

p(1) = 0

a(-1)²-(-1)²+(-1)+4 = 0

a-1-1+4 = 0

a = -2

So, the value of a is equal to -2.

Answer:

B

Step-by-step explanation:

∠ 3 and ∠ 8 are alternate angles and are congruent, then

6x + 3 = 4x + 29 ( subtract 4x from both sides )

2x + 3 = 29 ( subtract 3 from both sides )

2x = 26 ( divide both sides by 2 )

x = 13 → B

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

Explanation:

Think of 25 as 25/1 and 5 as 5/1

Choice E is really saying [tex]\frac{25}{1} \div \frac{5}{1}[/tex] which becomes [tex]\frac{25}{1} \times \frac{1}{5}[/tex]. Note the second fraction flips and we change to a multiplication sign.

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

Or you could think of it like this:

[tex]25 \times \frac{1}{5} = \frac{25}{1} \times \frac{1}{5} = \frac{25*1}{1*5} = \frac{25}{5} = 25 \div 5[/tex]

to help see why the answer is E.

Answer:

E

Step-by-step explanation:

Answer:

4/5

Step-by-step explanation:

for this problem you just add across so it would be 2+2= 4 but you don't add 5+5 because their the same number

Answer:

a is correct and b is incorrect

Cubcivtiv tyk ok givyog Answer: gg

Step-by-step explanation:

Answer:

D. 3.7 × 10⁶

Step-by-step explanation:

3.7 × 10⁶

3700000

Answer:

[tex]Q_3 = 56.45[/tex] --- The third quartile

[tex]Var = 370.18[/tex] -- Variance

Step-by-step explanation:

Given

[tex]Q_1 = 30.8[/tex] -- First quartile

[tex]Q_2 = 48.5[/tex] --- Median

[tex]\bar x = 42[/tex] --- Mean

[tex]Skp = -0.38[/tex] --- Coefficient of skewness

Solving (9): The third quartile [tex]Q_3[/tex]

This is calculated from

[tex]Skp = \frac{Q_1 + Q_3 - 2Q_2}{Q_3 - Q_1}[/tex]

So, we have:

[tex]-0.38 = \frac{30.8 + Q_3- 2*48.5}{Q_3 - 30.8}[/tex]

Cross Multiply

[tex]-0.38 (Q_3 - 30.8)= 30.8 + Q_3- 2*48.5[/tex]

Open bracket

[tex]-0.38Q_3 + 11.704= 30.8 + Q_3- 97.0[/tex]

Collect like terms

[tex]-0.38Q_3 -Q_3= 30.8 - 97.0- 11.704[/tex]

[tex]-1.38Q_3= -77.904[/tex]

Divide both sides -1.38

[tex]Q_3 = \frac{-77.904}{-1.38}[/tex]

[tex]Q_3 = 56.45[/tex] --- approximated

Solving (b): The variance

First, calculate the standard deviation from:

[tex]3IQR = 4SD[/tex]

[tex]IQR= Q_3 - Q_1[/tex]

So:

[tex]3IQR = 4SD[/tex]

[tex]3(Q_3 - Q_1) = 4SD[/tex]

Make SD the subject

[tex]SD = \frac{3}{4}(Q_3 - Q_1)[/tex]

[tex]SD = \frac{3}{4}(56.45 - 30.8)[/tex]

[tex]SD = \frac{3}{4}*25.65[/tex]

[tex]SD = \frac{3*25.65}{4}[/tex]

[tex]SD = \frac{76.95}{4}[/tex]

[tex]SD = 19.24[/tex]

So, the variance is:

[tex]Var = SD^2[/tex]

[tex]Var = 19.24^2[/tex]

[tex]Var = 370.18[/tex]

Answer:

answer is 1

Step-by-step explanation:

3 and 3 gets cancel .when you divide the same number answer is always 1

Answer:

b = 6 sqrt(2)

Step-by-step explanation:

Since this is right triangle, we can use the Pythagorean theorem

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

3^2 + b^2 = 9^2

9+b^2 = 81

b^2 = 81-9

b^2 = 72

Take the square root of each side

sqrt(b^2) = sqrt(72)

b = sqrt(36*2)

b = 6 sqrt(2)

Answer:

I think the answer is 11 because 244140625/(5^3*5^(-2)*5^11)

m=11

[tex] \huge \bf\pink{a} \purple{n} \pink{s} \purple{w} \pink{e} \purple{r}[/tex]

[tex]5m = 60 \\ m = \frac{60}{5} = 12[/tex]

Answer:

130 miles

Step-by-step explanation:

A scale drawing is a reduced form in terms of dimensions of an original image / building / object

the scale drawing is usually reduced at a constant dimension

scale of the drawing = original dimensions / dimensions of the scale drawing

Actual distance = 31/4 x 40

convert 31/4 to an improper fraction

to convert to improper fraction, take the following steps :  

1. Multiply the whole number  by the denominator

2. Add the numerator to the answer gotten in the previous step

3. divide the number gotten in the previous step by the denominator  

13/4 x 40 = 130 miles

Answer:

0 remainder 19

Step-by-step explanation:

Answer:

f(x) = - 2(x - 3)² + 2

Step-by-step explanation:

Given

f(x) = - 2x² + 12x - 16 ( factor out - 2 from the first 2 terms )

      = - 2(x² - 6x) - 16

To complete the square

add/subtract ( half the coefficient of the x- term)² to x² - 6x

f(x) = - 2(x² + 2(- 3)x + 9 - 9) - 16

     = - 2(x - 3)² + 18 - 16

     = - 2(x - 3)² + 2

Answer:

[tex]y=(x-3)^2-7[/tex]

Minimum

(-3,-7)

Step-by-step explanation:

[tex]y=x^2 -6x+2[/tex]

[tex]b=-6[/tex]

[tex]\frac{b}{2} =(-3)^2=9[/tex]

[tex]y+7=x^2-6x+9[/tex]

[tex]y=(x-3)^2-7[/tex]

-7 is a minimum.

Answer:

1272.3 yd^3

Step-by-step explanation:

Radius = 9 yd

V = radius^2 x pI x height = 9^2 x 3,14 x 5 = 1272.3 yd^3

Answer:.

Answer:1.we have dividend =divisor*quotient+remainder=

(x²+2x-1)(x²-2x+1)+(-4x+1)

=x²(x²-2x+1)+2x(x²-2x+1)-1(x²-2x+1)-4x+1

=x⁴-2x³+x²+2x³-4x²+2x-x²+2x-1-4x+1

=x⁴-4x²

Dividend is x⁴-4x².

2.

Multiplier is a-a²+1.

Answer:

[tex]i \: hope \: the \: above \: picture \\ helps[/tex]

[tex]have \: a \: nice \: day \: [/tex]

[tex]#Liliflim[/tex]

Answer:

1. 5.75 * 33 = $189.75

The bakers income is $189.75

2. 2 * y - 8 / 4 when y = 7

  2 * 7 - 8 / 4 = 12

3. 76 + 4 * y^2 + 1 when y = 3

   76 + 4 * 3^2 + 1 = 113

Answer:

y = (1/2)x - 2

Step-by-step explanation:

Slope intercept form: y = mx + c

x - 2y = 4

    -2y = -x + 4

[tex]\frac{-2y}{-2}=\frac{-x}{-2}+\frac{4}{-2}\\\\y = \frac{1}{2}x - 2[/tex]