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[Closed] I'm thick... kids maths help please

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[#9394164]

How do we work this out?

[IMG] [/IMG]


 
Posted : 21/06/2017 9:11 pm
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You need to un-move or un-delete the picture.


 
Posted : 21/06/2017 9:12 pm
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Common denominator is your friend ..

A/B + C/D = ( A*D + C* B ) / ( B * D)

I think, tis a long time since I did such algebra 😥


 
Posted : 21/06/2017 9:18 pm
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You want to get the two fractions to have the same denominator. In this case you can do this by multiplying both the numerator and the denominator of the first fraction by 6. Then you can add the numerators together.

Like 3/4 + 1/8 = (2*3)/(2*4) + 1/8 = 6/8 + 1/8 = 7/8


 
Posted : 21/06/2017 9:19 pm
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a/b + c/d = (a*d + b*c)/(b*d)


 
Posted : 21/06/2017 9:31 pm
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comic sans font.

Gah!


 
Posted : 21/06/2017 9:36 pm
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In this case you can do this by multiplying both the numerator and the denominator of the first fraction by 6

I think (hard to see on my phone) that the denominator on the first fraction is 5ca²

The second is 30ca³

So you need to multiply the top and bottom of the left fraction by 6a


 
Posted : 21/06/2017 9:38 pm
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i make it

7 * a^2 * b^2 * ( 24 * a * d + 1)/(30 * c * d ^3)

though i'm abit rusty at this sort of thing 🙂


 
Posted : 21/06/2017 9:40 pm
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Hmm. I got...

(168 * a^3 * b^2 * d + 7 * a^2 * b^2) / 30 * c * d^3


 
Posted : 21/06/2017 9:57 pm
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Curious - What age is this for?

Is the denominator ca or cd?


 
Posted : 21/06/2017 9:59 pm
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I got:

a²b²(7+168ad)/30cd³


 
Posted : 21/06/2017 10:02 pm
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year 10

cd not ca

Oh and the first fraction is being divided by the second. 🙁


 
Posted : 21/06/2017 10:03 pm
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7 goes into 168 24 times btw 😀


 
Posted : 21/06/2017 10:05 pm
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7a²b²(1+24ad)/30cd³

Is that better?


 
Posted : 21/06/2017 10:15 pm
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we got that bit Klunky..... but what about the letters? I reckon the top line is 24a....


 
Posted : 21/06/2017 10:17 pm
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using the formula for adding 2 fractions

a/b + c/d = (a*d + b*c)/(b*d)

gives

840 * a^3 * b^2 * c * d^3 + 35 * a^2 * b^2 * c * d^2
_____________________________________________________
150 * c^2 * d^5

divide top and bottom by c , d^2 and 5 gives

168 * a^3 * b^2 * d + 7 * a^2 * b^2
___________________________________
30 * c * d^3

the top reduces to... (168 * a^3 * b^2 * d) = (7 * a^2 * b^2) * ( 24 * a * d)

7 * a^2 * b^2 * ( 24 * a * d + 1)
__________________________________
30 * c * d^3


 
Posted : 21/06/2017 10:21 pm
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It's amazing how much you forget. I did a-level maths but then spent the last 20 ish years in the bike trade and ive spent ages tryning remember


 
Posted : 21/06/2017 10:21 pm
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using the formula for adding 2 fractions

yes but we're diving the fractions...


 
Posted : 21/06/2017 10:23 pm
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If that's a divide symbol, then the answer is 24ad.

To divide by a fraction, you invert it (take the reciprocal) and then multiply.

You would then get 840a³b²cd³ / 35a²b²cd², which simplifies to the above.


 
Posted : 21/06/2017 10:25 pm
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MUCH easier if its divide

( A / B ) / ( C / D ) = ( A / B ) * ( D / C ) = ( A * D ) / ( B * C )


 
Posted : 21/06/2017 10:28 pm
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If that's a divide symbol, then the answer is 24ad.

WHAT?!!! That's what I [really really actually] thought it was!


 
Posted : 21/06/2017 10:28 pm
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post a better image next time 😀


 
Posted : 21/06/2017 10:28 pm
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WHAT?!!! That's what I [really really actually] thought it was!

Absolute total bollix 🙂


 
Posted : 21/06/2017 10:29 pm
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I did honest Miss!


 
Posted : 21/06/2017 10:32 pm
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Thanks guys... think I learnt something there - that I do hate maths!


 
Posted : 21/06/2017 10:34 pm
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Edit: We've decided we still don't get it so there's some work to be done!


 
Posted : 21/06/2017 10:48 pm
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Dividing by a fraction is (as said above) the same as multiplying by the reciprocal, so turn the second fraction upside down and multiply!

You can then cross out anything that appears on the top and the bottom:

All the bs cancel, so do all the cs: you're left and a and a d! For the numbers you're left with 28x30 divided by 5x7, so 24.

As above, 24ad ftw!


 
Posted : 22/06/2017 6:17 am
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I get the same answer as sockpuppet,


 
Posted : 22/06/2017 12:05 pm
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24ad

cross multiply


 
Posted : 22/06/2017 12:31 pm
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comic sans font.

Gah!

It is often used in education as it is more dyslexia-friendly...

[url= https://www.dyslexic.com/fonts/ ][i]Many dyslexic people also find it easier to read a font that looks similar to hand writing as they are familiar with this style[/i][/url]


 
Posted : 22/06/2017 12:35 pm
 Aidy
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for b,c ? 0


 
Posted : 22/06/2017 12:39 pm
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I think we're all missing the big picture here*, which is, have you used a phone to take a screenshot of a PC, which has a keyboard with a dedicated "print screen" button on it?

(* - literally)


 
Posted : 22/06/2017 12:39 pm
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with a dedicated "print screen" button

Unless they (nasty Microsoft) have changed it recently, don't you then have to figure our a way of then 'saving' the captured image? Unlike the Wonders of Mac where the whole screen (Command/Shift/3) or select Command/Shift/4 to open a marquee so you can select the area of the screen you want to screenshot then have it conveniently saved to your desktop as a neat little .png file?


 
Posted : 22/06/2017 12:58 pm
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Unless they (nasty Microsoft) have changed it recently, don't you then have to figure our a way of then 'saving' the captured image?

PrtSc sends the image to the clipboard. You can then paste straight into imgur without needing to save anything anywhere locally (as I was delighted to discover by accident the other day). Or dump it into Paint and crop / save it if you want.

Windows 10 also has the [url= https://support.microsoft.com/en-us/instantanswers/671b2932-1274-452a-905b-f7ed3c7d8818/open-snipping-tool-and-take-a-screenshot ]Snipping Tool[/url] which is essentially what you describe (only better).


 
Posted : 22/06/2017 1:16 pm
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Seems it's in W7 too, I've just checked on this machine here. Win-S is the hotkey. (It might be part of OneNote though... ?)


 
Posted : 22/06/2017 1:22 pm
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So you do still need to paste the file and save it in another programme?


 
Posted : 22/06/2017 1:32 pm
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Was your kid's problem with division of fractions or with the algebra?

For division of fractions: [b]Keep[/b] the first fraction, [b]change[/b] the sign to a multiply, [b]flip[/b] the second fraction. [b]Keep[/b], [b]change[/b], [b]flip[/b].


 
Posted : 22/06/2017 1:39 pm
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So you do still need to paste the file and save it in another programme?

Snipping Tool lets you save the area of screen selected as an image file.


 
Posted : 22/06/2017 1:40 pm
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I believe Win-PrtSc saves an image directly to the Pictures folder in later versions of Windows too (from W8 onwards).


 
Posted : 22/06/2017 1:48 pm
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Is the answer:

24ad?


 
Posted : 22/06/2017 1:50 pm
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Just checked the rest of the thread and it appears I got it right.

Quite pleased with that, did it completely in my head.


 
Posted : 22/06/2017 1:53 pm
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Cougar... yes I did. She was still doing still on the PC and i didn't want to disturb her.

Was your kid's problem with division of fractions or with the algebra?

For division of fractions: Keep the first fraction, change the sign to a multiply, flip the second fraction. Keep, change, flip.


Probably both. But when I mentioned [s]KFC[/s] KCF she remembered. It was probably the algebra that confused [s]me[/s] her.

Took me five goes to pass my maths O level - my housemaster was so happy when I finally passed that he gave me £5 (lot of money back then) to go to the school bar (yes, our school had its own pub!) 🙂


 
Posted : 22/06/2017 2:09 pm
 DezB
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[i]It's amazing how much you [s]forget[/s][/i] are taught at school that's NEVER NEEDED FOR ANYTHING ELSE BUT SCHOOL MATHS![i]. I did a-level maths but then spent the last 20 ish years in the bike trade and ive spent ages tryning remember[/i]


 
Posted : 22/06/2017 2:36 pm
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It's amazing how much you forget are taught at school that's NEVER NEEDED FOR ANYTHING ELSE BUT SCHOOL MATHS!

... and appearing to be clever on a mountain biking forum. (-:


 
Posted : 22/06/2017 2:46 pm
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Dividing one fraction by another is quite useful, no?

I use the maths that I was taught at school all the time.


 
Posted : 22/06/2017 2:52 pm
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