4b) Work out the mean and standard deviation of the following: picture included

Note: I ended up with the simultaneous equations, which are correct according to the markscheme BUT the answers I got upon solving them were incorrect.
μ = 170 + 1.6449σ
μ = 180 - 0.8416σ

What I got after solving these were:
μ = 169.5306859
σ = 12.44864932

But according to the markscheme, I should have gotten:
μ = 176.615...
σ = 4.021...

Can someone explain to me where I've gone wrong?

Using algebraic equations:

the number of sessions that will give same cost for both plans is: 1

the cost is: $96

Translate the situation into algebraic equations.

Equation for total cost of the first plan:

y = 41x + 55

Equation for the total cost of the second plan:

y = 46x + 50

To find the number of sessions that would yield same cost for both plans, make both equations equal to each other and solve for x.

41x + 55 = 46x + 50

41x - 46x = - 55 + 50

-5x = -5

x = 1

For a session, both plans will yield the same cost.

The cost 1 session will yield for both:

41x + 55 = 46x + 50

41(1) + 55 = 46(1) + 50

96 = 96

Therefore, using algebraic equations:

the number of sessions that will give same cost for both plans is: 1

the cost is: $96

Learn more about algebraic equations on:

https://brainly.com/question/10612698

Answer:

J = 90

John has 90 dollars.

Step-by-step explanation:

We need to find how much money John has. To find how much J equals we need to break it down.

We already know that Steven has 150 dollars. We also know that he has 30 less than two times the amount John has.

Steven has 30 less than two times the amount John has.

So 150 + 30 = 180

180 is two times the amount John has.

Because 180 is two times the amount John has we need to divide by two.

180 ÷ 2 = 90.

J = 90. Therefore John has 90 dollars.

This question was tricky! I hope I helped a little! Have a great day!!

Answer: The two companies never charge the same amount to rent a bicycle for the same number of hours.

Answer:

3/4 is in it's simplest form

Step-by-step explanation:

3/4 cannot be simplified any more, so it is at it's simplest form

Answer:

  y = -1/7x +20/7

Step-by-step explanation:

Solve for y.

  7y = -x +20 . . . . . subtract x from both sides to get the y-term by itself

  y = -1/7x +20/7 . . . . divide both sides by the coefficient of x

In this form, you can see ...

Answer:

y=-1/7x+20/7

Step-by-step explanation:

So they are asking us to put x+7y=20 into slop-intercept form (y=mx+b).

They're pretty much just asking us to solve for y.

x+7y=20

7x=20-x (Subtract x from both sides)

y=20-x/7 (Divide 7 on both sides to isolate y)

y=20/7-1/7x

y=-1/7x+20/7

So..

m=-1/7

b=20/7

Hope this helps :)

[tex]\\ \sf\Rrightarrow LSA=2(h)(l+b)[/tex]

[tex]\\ \sf\Rrightarrow LSA=2(18)(6+4)[/tex]

[tex]\\ \sf\Rrightarrow LSA=36(10)[/tex]

[tex]\\ \sf\Rrightarrow LSA=360in^2[/tex]

Answer:

The amount of tax is £178.34, and the full total is £1142.34.

Step-by-step explanation:

Use a calculator to find 18.5 percent of 964, giving us the answer we need. You may add this to the cost before tax to find the exact price after tax.

The amount of tax that is added to the cost of the computer is

£178.34.

A compulsory contribution to state revenue, levied by the government on workers' income and business profits, or added to the cost of some goods, services, and transactions.

Given is that a computer costs £964. A tax of 18.5% is then added to the cost of the computer.

Assume the amount of tax that is added to the cost of the computer is

£{x}. Then, we can write the equation as -

{x} = 18.5% of 964

{x} = (18.5/100) x 964

{x} = 178.34

Therefore, the amount of tax that is added to the cost of the computer is

£178.34.

To solve more questions on percentage, visit the link below -

brainly.com/question/24159063

#SPJ12

Answer:

2×2=4

9x+2=11x

1-6x=4x

x²-4=16

=16¹⁵x

The new price of the scooter will be:

= $50 - (20% × $50)

= $50 - $10

= $40

The sale price of the football will be:

= 35% × $60

= $21

I have like 27 missing assignments

Answer:

five times a number plus two.

Explanation:

Here's one way:

At vertex A, draw the vertical angle to the given angle 4. That is, extend AC, rather than AB to show the exterior angle at that vertex.

Now, collapse triangle to one with zero area, so that vertices A, B, C lie on top of each other. You can do this using a dilation scale factor f such that f→0.

The result is that the exterior angles divide the circular space around point ABC into three parts that sum to 360°. Essentially, we have copied each of the exterior angles to the same vertex.

The sum of the measures of the exterior angles is 360°.

_____

Additional comment

This identical approach can be used to show the sum of exterior angles around any convex polygon is always 360°.

z²-2i=0

Answer:

Solution given:

z⁴=-4

doing square root on both side

[tex]\sqrt{z⁴}=\sqrt{2²*-1}[/tex]

we know i²=-1

substituting i² we get

z²=[tex]\sqrt{2²*i²}[/tex]

z²=2i

z²-2i=0 is a required answer. where

z² and 2 is real number.

Answer:

  z = {-1 -i, -1 +i, 1 -i, 1 +i}

Step-by-step explanation:

Using Euler's formula, we can write the equation as ...

  z^4 = 4e^(i(π +2πn)) . . . . . . where n is any integer

Then the 4th root is ...

  z = (√2)e^(i(π +2πn)/4 = (√2)e^(i(π/4 +nπ/2)) . . . . . for n = 0–3

  z = √2(cos(π/4+nπ/2) +i·sin(π/4 +nπ/2)) . . . . . for n = 0–3

  z = ±1 ±i

  z = {1 +i, -1 +i, -1 -i, 1 -i}

_____

Additional comment

Values of n are only needed in the range 0–3, because the answers repeat for values other than those.

Answer: 28 y

Step-by-step explanation: All you really have to do is multiply 7 by 4y. 7(4y) 28y

Answer:

#1 and #3

Step-by-step explanation:

Answer:

See image

Step-by-step explanation:

Use Pythagorean Theorem

a^2 + b^2 = c^2

See image

Answer:

8762

Step-by-step explanation:

Exponential decay equation

Initial = 18000

Rate 6% = 0.06

Time = 12

Answer:

$8567

Step-by-step explanation:

In the image the answer is given.

Formula of depreciation is used in the answer.

Answer:

Hey mate....

Step-by-step explanation:

This is ur answer....

Hope it helps!

Brainliest pls!

Follow me! :)

Answer:

The answer would be A

Step-by-step explanation:

a. the pumpkins maximum height is 204.06 feet and it hits the ground after 7.01 seconds.

Answer:

45 ft²

Step-by-step explanation:

I hope this helps!

Answer:

y-6=3/5(x-6)

Step-by-step explanation:

Answer:

I think the correct answer is c hope this helps

Answer:

5 over 1 (5/1) or 5.

Step-by-step explanation:

y is adding 5 each time and x is adding 1 each time.

Not sure about the equation part though.

Answer:

C. Public colleges are cheaper for in-state residents.

Step-by-step explanation:

Answer:

Axis interception points of -52 :

Y intercepts : (0,-52 )

Answer:Given that 3 persons can weave 168 shawls in 14 days. Then, Shawls are woven in 1 day by the 3 men = 168/14 = 12. Shawls are woven in 1 day ...

Step-by-step explanation:

Answer:

5/4

Step-by-step explanation:

The original line is

7 - 3 / 4 - 9

4/-5, so the slope is -4/5

Perpendicular means the opposite sign and reciprocal.

5/4

Answer:

D

Step-by-step explanation:

The line starts at 10 so I think it's that

Answer:

Slope of a line

m = \frac{\text{rise}}{\text{run}} = \frac{y_2 - y_1}{x_2 - x_1}

m = slope

(x_1, y_1) = coordinates of first point in the line

(x_2, y_2) = coordinates of second point in the line

Step-by-step explanation:

Khan Academy

Slope review | Algebra (article) | Khan Academy