# Can ANYONE help me with these maths questions?

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Im gonna break down in a second, is there anyone who can help take me through these, or at least a couple of them?

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#2

Q11. My thoughts are...

A:B is 2:5 and C: D is 3:1, C and D share twice as much money, so their ratio will be doubled, thus A:B:C: Dis 26:2

Q12. Draw the triangle labelling the sides opposite, hyp and adj. QR is op, PQ hyp, PR adj. The length of QR is 0.6 and the length of PQ is 1. To find the size of the angle it'll be sin -1 or 0.6/1 to give an answer of 36.9 degrees.

Q16. Substitute 2 in and then substitute 3 in to the formula given. One will give you a positive answer, the other negative. The change of sign shows a solution lies between the two.

For part b rearrange to get x^3 = 3x^2 + 3 and then cube root both sides.

Hope I've helped a little bit, hard to explain

A:B is 2:5 and C: D is 3:1, C and D share twice as much money, so their ratio will be doubled, thus A:B:C: Dis 26:2

Q12. Draw the triangle labelling the sides opposite, hyp and adj. QR is op, PQ hyp, PR adj. The length of QR is 0.6 and the length of PQ is 1. To find the size of the angle it'll be sin -1 or 0.6/1 to give an answer of 36.9 degrees.

Q16. Substitute 2 in and then substitute 3 in to the formula given. One will give you a positive answer, the other negative. The change of sign shows a solution lies between the two.

For part b rearrange to get x^3 = 3x^2 + 3 and then cube root both sides.

Hope I've helped a little bit, hard to explain

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#3

For the first one:

To make it easier, turn them into real numbers. To decide how much money Carl and Donna should share, you want to find a number that can be divided by both 7 (2 + 5, the parts you need to divide Anna and Bill's money into), 2 (because it's exactly double Anna and Bill's amount of money) and 4 (3 + 1, the parts you need to divide Carl and Donna's money into). The lowest number is 28.

So say Carl and Donna have £28, and Anna and Bill have £14 (exactly half). Do you know how to work it out from there?

What are these problems for?

To make it easier, turn them into real numbers. To decide how much money Carl and Donna should share, you want to find a number that can be divided by both 7 (2 + 5, the parts you need to divide Anna and Bill's money into), 2 (because it's exactly double Anna and Bill's amount of money) and 4 (3 + 1, the parts you need to divide Carl and Donna's money into). The lowest number is 28.

So say Carl and Donna have £28, and Anna and Bill have £14 (exactly half). Do you know how to work it out from there?

What are these problems for?

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(Original post by

For the first one:

To make it easier, turn them into real numbers. To decide how much money Carl and Donna should share, you want to find a number that can be divided by both 7 (2 + 5, the parts you need to divide Anna and Bill's money into), 2 (because it's exactly double Anna and Bill's amount of money) and 4 (3 + 1, the parts you need to divide Carl and Donna's money into). The lowest number is 28.

So say Carl and Donna have £28, and Anna and Bill have £14 (exactly half). Do you know how to work it out from there?

What are these problems for?

**youknownothing7**)For the first one:

To make it easier, turn them into real numbers. To decide how much money Carl and Donna should share, you want to find a number that can be divided by both 7 (2 + 5, the parts you need to divide Anna and Bill's money into), 2 (because it's exactly double Anna and Bill's amount of money) and 4 (3 + 1, the parts you need to divide Carl and Donna's money into). The lowest number is 28.

So say Carl and Donna have £28, and Anna and Bill have £14 (exactly half). Do you know how to work it out from there?

What are these problems for?

These are practice questions I'm doing for improvement but I cant find the mark scheme anywhere for these questions, lol.

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#5

(Original post by

I understand what you've taken me through, but I don't know how to continue it. Would I have to divide 28 by 2 and 5 or something?

These are practice questions I'm doing for improvement but I cant find the mark scheme anywhere for these questions, lol.

**lucci77**)I understand what you've taken me through, but I don't know how to continue it. Would I have to divide 28 by 2 and 5 or something?

These are practice questions I'm doing for improvement but I cant find the mark scheme anywhere for these questions, lol.

Carl and Donna share the £28 in a ratio of 3:1, as we're told in the question, so how much do they get each?

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#6

q14) I got 720. This is not my strongest point but my logic was:

on Monday, he had

on Tuesday, he has already picked one so he has

on Wednesday, he has

so I did

on Monday, he had

**10**different options to choose fromon Tuesday, he has already picked one so he has

**9**different options to choose fromon Wednesday, he has

**8**different options to choose fromso I did

**10x9x8 = 720**because I assumed he could pick the different options in a random order
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(Original post by

Determined to self-improve, good on you

Carl and Donna share the £28 in a ratio of 3:1, as we're told in the question, so how much do they get each?

**youknownothing7**)Determined to self-improve, good on you

Carl and Donna share the £28 in a ratio of 3:1, as we're told in the question, so how much do they get each?

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#8

For the second question, sin is opposite divided by hypotenuse.

Opposite QPR is QR. The hypotenuse (the longest side) is PQ. So sinQPR is QR divided by PQ.

Assign a random number to be PR (5 would be a convenient one). QR will be 60% of that, and you can use Pythagoras to work out PQ.

Opposite QPR is QR. The hypotenuse (the longest side) is PQ. So sinQPR is QR divided by PQ.

Assign a random number to be PR (5 would be a convenient one). QR will be 60% of that, and you can use Pythagoras to work out PQ.

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#9

(Original post by

21:7, right?

**lucci77**)21:7, right?

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(Original post by

Yep. And how much will Anna and Bill have?

**youknownothing7**)Yep. And how much will Anna and Bill have?

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#11

(Original post by

4:10 ))))

**lucci77**)4:10 ))))

I went through the second question above and MystG123 has explained the third one very well.

The last one is an incredibly dull question imo. For a), make the whole equation equal to y and imagine plotting it on a graph. When x=2, y will equal -1. When x=3, y will equal 3. So at some point between them, the curve must pass through a point where y = 0.

Can you do b?

(Is this GCSE or A Level stuff? I struggle to remember)

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#12

(Original post by

Im gonna break down in a second, is there anyone who can help take me through these, or at least a couple of them?

**lucci77**)Im gonna break down in a second, is there anyone who can help take me through these, or at least a couple of them?

Here's the reason why there's a change in signs. Have a look at the diagram below,

Suppose this graph. You can see the root lies in between and .

But how do we prove this?

Substitute in the values and you'll see the sign change.

So and . Look at the diagram, you have a positive value at and a negative value at therefore there is a root between and because this is where the curve crosses the axis.

Also adding onto Part b from the user I mentioned,

You need to obtain the equation , you can work backwards so cube the whole equation to obtain so you can see that you want to make the subject first then cube root the whole equation to make the subject as required.

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#13

(Original post by

Q11. My thoughts are...

A:B is 2:5 and C: D is 3:1, C and D share twice as much money, so their ratio will be doubled, thus A:B:C: Dis 26:2

Q12. Draw the triangle labelling the sides opposite, hyp and adj. QR is op, PQ hyp, PR adj. The length of QR is 0.6 and the length of PQ is 1. To find the size of the angle it'll be sin -1 or 0.6/1 to give an answer of 36.9 degrees.

Q16. Substitute 2 in and then substitute 3 in to the formula given. One will give you a positive answer, the other negative. The change of sign shows a solution lies between the two.

For part b rearrange to get x^3 = 3x^2 + 3 and then cube root both sides.

Hope I've helped a little bit, hard to explain

**futurematters**)Q11. My thoughts are...

A:B is 2:5 and C: D is 3:1, C and D share twice as much money, so their ratio will be doubled, thus A:B:C: Dis 26:2

Q12. Draw the triangle labelling the sides opposite, hyp and adj. QR is op, PQ hyp, PR adj. The length of QR is 0.6 and the length of PQ is 1. To find the size of the angle it'll be sin -1 or 0.6/1 to give an answer of 36.9 degrees.

Q16. Substitute 2 in and then substitute 3 in to the formula given. One will give you a positive answer, the other negative. The change of sign shows a solution lies between the two.

For part b rearrange to get x^3 = 3x^2 + 3 and then cube root both sides.

Hope I've helped a little bit, hard to explain

This is basically it.

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(Original post by

Yep, so the ratio is 4 : 10 : 7 : 21

I went through the second question above and MystG123 has explained the third one very well.

The last one is an incredibly dull question imo. For a), make the whole equation equal to y and imagine plotting it on a graph. When x=2, y will equal -1. When x=3, y will equal 3. So at some point between them, the curve must pass through a point where y = 0.

Can you do b?

(Is this GCSE or A Level stuff? I struggle to remember)

**youknownothing7**)Yep, so the ratio is 4 : 10 : 7 : 21

I went through the second question above and MystG123 has explained the third one very well.

The last one is an incredibly dull question imo. For a), make the whole equation equal to y and imagine plotting it on a graph. When x=2, y will equal -1. When x=3, y will equal 3. So at some point between them, the curve must pass through a point where y = 0.

Can you do b?

(Is this GCSE or A Level stuff? I struggle to remember)

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#17

does anybody have the mark scheme for this paper? if so could they attach it or send the link pls. tyy xx

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#18

(Original post by

would you do inverse sin for question 12???

**JanNotYourMan**)would you do inverse sin for question 12???

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#19

16.b. X^3= 3X^2-3 take all other terms to other side

Take cube roots on both sides

You will get your answer right

Take cube roots on both sides

You will get your answer right

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#20

(Original post by

No, it only asks you for what sinQPR is, not QPR itself, so there’s no need to do inverse sin.Remember also that sin is OPPOSITE over hypotenuse, not adjacent. I get 0.514 to 3 significant figures.

**youknownothing7**)No, it only asks you for what sinQPR is, not QPR itself, so there’s no need to do inverse sin.Remember also that sin is OPPOSITE over hypotenuse, not adjacent. I get 0.514 to 3 significant figures.

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