Can someone please help me with questions 12 through 14 with the answer correct I was trying but I don’t know what I put down is right it’s a beat confuse anyone please

Answer:

[tex]t = 0.875[/tex]

Step-by-step explanation:

Given

Brand A            Brand B

[tex]n_ 1= 12[/tex]               [tex]n_2 = 12[/tex]

[tex]\bar x_1 = 21.8[/tex]            [tex]\bar x_2 = 18.9[/tex]

[tex]\sigma_1 = 8.7[/tex]              [tex]\sigma_2 = 7.5[/tex]

Required

Determine the test statistic (t)

This is calculated as:

[tex]t = \frac{\bar x_1 - \bar x_2}{s\sqrt{\frac{1}{n_1} + \frac{1}{n_2}}}[/tex]

Calculate s using:

[tex]s = \sqrt{\frac{(n_1-1)*\sigma_1^2+(n_2-1)*\sigma_2^2}{n_1+n_2-2}}[/tex]

The equation becomes:

[tex]s = \sqrt{\frac{(12-1)*8.7^2+(12-1)*7.5^2}{12+12-2}}[/tex]

[tex]s = \sqrt{\frac{1451.34}{22}}[/tex]

[tex]s = \sqrt{65.97}[/tex]

[tex]s = 8.12[/tex]

So:

[tex]t = \frac{\bar x_1 - \bar x_2}{s\sqrt{\frac{1}{n_1} + \frac{1}{n_2}}}[/tex]

[tex]t = \frac{21.8 - 18.9}{8.12 * \sqrt{\frac{1}{12} + \frac{1}{12}}}[/tex]

[tex]t = \frac{21.8 - 18.9}{8.12 * \sqrt{\frac{1}{6}}}[/tex]

[tex]t = \frac{21.8 - 18.9}{8.12 * 0.408}}[/tex]

[tex]t = \frac{2.9}{3.31296}}[/tex]

[tex]t = 0.875[/tex]

Answer:

There are 160 cats at the store.

Step-by-step explanation:

There are 40 black cats, which is 25% of all the cats. You are trying to find all the cats at the store, or 100% of the cats at the store. So:

40 = 25%

40(4) = 25% (4)

160 = 100%

There are 160 cats at the store.

Answer:

160

Step-by-step explanation:

25%=1/4=0.25

=40×4

=160

Answer:

A, B and D are the answers.

Answer:

A, B, D.

Step-by-step explanation:

Answer:

5). x = 11.9°

6). x = 27.2°

Step-by-step explanation:

5). By applying cosine rule in the given triangle,

   cos(32)° = [tex]\frac{\text{Adjacent side}}{\text{Hypotenuse}}[/tex]

   cos(32)° = [tex]\frac{x}{14}[/tex]

    x = 14cos(32)°  

    x = 11.87

    x ≈ 11.9°

6). By applying sine rule in the given triangle,

    sin(54°) = [tex]\frac{\text{Opposite side}}{\text{Hypotenuse}}[/tex]

    sin(54°) = [tex]\frac{22}{x}[/tex]

     x = [tex]\frac{22}{\text{sin(54)}}[/tex]

     x = 27.19°

     x ≈ 27.2°

Answer:

(x+2.25) ×24

This is how it is written

Answer:

Step-by-step explanation:

y = 24*(x + 2.25)

There, that's an algebraic expression for 24 times the sum of a number and 2.25.

$100 - $20 = $80

Understand?

Answer:

x=27

Step-by-step explanation:

Hey there!

the exterior angles of a quadrilateral add up to equal 360

so 360=2x+40+4x+3x+x+50

step 1 combine like terms

2x+4x+3x+x=10x

50+40=90

now we have

360=10x+90

step 2 subtract each side by 90

360-90=270

90-90 cancels out

now we have 270=10x

step 3 divide each side by 10

270/10=27

we're left with

x=27

Answer:

you have to do the sales tax, times the price $3.10

then you add the $3.10 to the original price which is $41.85

Step-by-step explanation:

Answer:

B. L and N

Step-by-step explanation:

Let's solve each system

✔️System L:

3x + y = 8 => Eqn. 1

x - 4y = -6 => Eqn. 2

x = -6 + 4y

Substitute x = (-6 + 4y) in eqn. 1

3(-6 + 4y) + y = 8

-18 + 12y + y = 8

-18 + 13y = 8

13y = 8 + 18

13y = 26

y = 26/13

y = 2

Substitute y = 2 into Eqn. 2

x - 4y = -6

x - 4(2) = -6

x - 8 = -6

x = -6 + 8

x = 2

Solution to system L = (2, 2)

✔️System M:

4x - 3y = 2 => Eqn. 1

5x - 4y = -30 => Eqn. 2

Multiply eqn 1 by 5, and eqn. 2 by 4

20x - 15y = 10

20x - 16y = -120

Subtract

y = 130

Substitute y = 130 into eqn. 1

4x - 3(130) = 2

4x - 390 = 2

4x = 2 + 390

4x = 392

x = 392/4 = 98

Solution to system M = (98, 130)

✔️System N:

4x - 3y = 2 =>Eqn. 1

2x - 8y = -12 => Eqn. 2

Multiply Eqn. 1 by 2, and eqn. 2 by 4

8x - 6y = 4

8x - 32y = -48

Subtract

26y = 52

y = 52/26

y = 2

Substitute y = 2 into eqn. 1

4x - 3(2) = 2

4x - 6 = 2

4x = 2 + 6

4x = 8

x = 8/4

x = 2

Solution to system N = (2, 2)

First question seems incomplete :

Answer:

40 ways

Step-by-step explanation:

Question B:

Number of boys = 6

Number of girls = 4

Number of people in committee = 3

Number of ways of selecting committee with atleast 2 girls :

We either have :

(2 girls 1 boy) or (3girls 0 boy)

(4C2 * 6C1) + (4C3 * 6C0)

nCr = n! ÷ (n-r)!r!

4C2 = 4! ÷ 2!2! = 6

6C1 = 6! ÷ 5!1! = 6

4C3 = 4! ÷ 1!3! = 4

6C0 = 6! ÷ 6!0! = 1

(6 * 6) + (4 * 1)

36 + 4

= 40 ways

Answer:

Yes, they are equal because of distributive property

Step-by-step explanation:

6(1 + m) = 6 + 6m

Answer:

A and C

Step-by-step explanation:

20) Since the triangles are similar, you can say that 98 corresponds to 42 and 77 corresponds to 3x+6, because of this you can write an equation ((98/77)(3x-6) =42) and then simplify to get x = 13.

21) Since ABC and DFE are similar, we can say that 2x+2 corresponds to x+3 and 24 corresponds to 16. You can write this as the equation (24/2x+2)(x+3) = 16 and simplify to get x=5.

I hope this helps :)

Answer:

6.c 7.c 8. b 9. a 10. a

Step-by-step explanation:

6=c as 39.10-19.56

7. 89.2-78.6

8. 8.03-5.1

9. 40.98-15.6

10.55.6-47.5

Answer:

65 percent chance right

Step-by-step explanation:

so she opens it 13 out of 20 times, so divide 13 by 20 and you get it

Answer:

Q.1 lx²+mx

=x(lx+m)

Q.2 x² - ax - bx + ab

= x(x - a) - b(x - a)

=(x - b)(x - a)

Q.3 6ab - b²+ 12ac - 2bc

= b(6a - b) - 2a(6a - b)

=(b - 2a)(6a - b)

Answer:

the answer is 60 because 2 times 30 is 60

Step-by-step explanation:

Answer:

33.69[tex]\pi[/tex] or 105.83

Step-by-step explanation:

Volume for a cylinder is

V= [tex]\pi r^{2}h[/tex]

we need to find the radius from the base

B = 2[tex]\pi[/tex]r

B= 3.5/2 = 1.75

V =[tex]\pi 1.75^{2}*11[/tex]

V =  33.69[tex]\pi[/tex] or 105.83 depending if you want it in pi for or not

Answer:

C

Step-by-step explanation:

4000 mcmcnxmamnxmxmnxnxns

4.0/5

136

The answer is x = -8/9.

Hope you have a good rest of your day. :)

Answer:

B. [tex]x=-\frac{8}{9}[/tex]

Step-by-step explanation:

edge 2021

:) Good luck, loves!

Answer:

number of minutes

Step-by-step explanation:

Answer:

C

Step-by-step explanation:

If you graph the points, count boxes from the orgin (0,0).

You will have to go 3 to the right (on x), and up 6 (on y).

Answer:

the area of the floor that is not carpeted 19 m squared

Step-by-step explanation:

7x5 =35  m squared = area of the floor

 4x4 = 16 squared =(area of the carpeted floor)

35-16 = 19

Answer:

About V≈113.1ft³

Step-by-step explanation:

This is because alternate exterior angles are congruent when we have parallel lines like this.

Angle 2 and angle 8 are both outside the parallel lines, so that's what makes them exterior angles. Also, they are on alternating sides of the transversal line (angle 2 on the left, angle 8 on the right). So that's where the "alternating" comes from. The other pair of alternate exterior angles is angle 1 and angle 7.