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## #1 Re: Help Me ! » surd question help needed » 2014-04-17 06:44:08

Ok bobbym thanks and I, ll do that and post by tomorrow hopefully if holidays dont devour me up -:)

## #2 Re: Help Me ! » surd question help needed » 2014-04-17 02:26:45

Sorry for the delay.....it is a 5......thanks

## #3 Re: Help Me ! » surd question help needed » 2014-04-16 05:25:51

Thank you lots bobbym your an amazing help as I try to come to grips with all this new information.  If you haven't time to look at the second question I posted in my Dropbox no worries, im happy for help with question ,  but if you can great.....-:)

## #4 Re: Help Me ! » surd question help needed » 2014-04-15 09:48:25

https://www.dropbox.com/s/4mbvmuy64j1ym … 408_01.jpg

## #5 Re: Help Me ! » surd question help needed » 2014-04-15 09:22:35

https://www.dropbox.com/s/ddpiqt96ptjla … 447_01.jpg

The link will explain better sorry for the torturous sentence in prevoius post.....I think ive got surds flu.....agggghhhh

## #6 Help Me ! » surd question help needed » 2014-04-15 07:55:26

silverpuma
Replies: 12

Im making progress with my surds diet......yum yum but one has stuck in my throat.  I need a step by step of how you arrive at my textbook answer of 5root2 over 2  the question is ........The sq root18 minus 1 over sq root 2     thanks again for your patience.

## #7 Re: Help Me ! » standard form question I got wrong ....need some help please. » 2014-04-10 09:54:30

bobbym wrote:

Soon you will get to Absolute value and Surds, then they will combine an Absolute value and a Surd into AbSurd. Just a little geek humor.

He he.....

Even the name "surds" who thought that one up......

## #8 Re: Help Me ! » standard form question I got wrong ....need some help please. » 2014-04-10 08:36:18

Great bobbym all makes sense now. I could kick myself not getting this right but the learning goes on. Irrational and rational numbers next with surds after that yum yum.  Thanks for the help....

## #9 Help Me ! » standard form question I got wrong ....need some help please. » 2014-04-10 06:53:31

silverpuma
Replies: 5

https://www.dropbox.com/s/sn00ksxbx9hn6 … 193709.jpg

Hi guys,  I'm on standard form now and got all my exam type questions from the text book right until this last one (see above) the answer is 2167 seconds as per the answer sheet but could you show your working out for me as I must be making a wrongs step along the way.  Thanks as always

Ooops it question 4 the planets

## #10 Re: Help Me ! » Ratio question has my blood pressure in the red......-:) » 2014-04-04 06:50:22

Thanks bobbym I'll have a good think about this.  I confess it's still not overly clear in my mind.

## #11 Help Me ! » Ratio question has my blood pressure in the red......-:) » 2014-04-04 06:24:03

silverpuma
Replies: 3

Im on ratios in my working through the ccea gcse higher textbook and im really enjoying it.  ON ratios I sailed through the summary questions and exam questions without too much trouble and was happy I had a good grasp.....until.....this question stumped me.

Question: A prize is divided between three people P, Q and R.  If the ratio of P's share to Q's share is 3:1 and of Q's share to R's share is 2:5 , calculate the ratio of P's share to R's share.

The answer is 6:5 as per the book but I need someone to explain ....how...the steps to this answer is arrived at.    Many thanks for your patience with this old codger...

## #12 Re: Help Me ! » If you know the sum of the factors of a number, what the number? » 2014-03-06 16:17:04

Thanks bobbym.  So from what you said, I'm assuming that the textbook authors probably added this question to get the reader (me) to do what I did, and just figure it out with a few trys.  I enjoyed this as it made me stop and try different things albeit to no avail in the end but the ponder was good.  Though on the other hand it did leave me a bit perturbed as it looked to begin with a fairly straight forward question that after a bit of thinking through I thought I will be able to come up with a formula or number of steps to answer this question and others like it without the tests I had to do.  More of a definitive method.

I had thought I must be missing something easy since I expected the summary questions at the end of the chapter (where this question was) would have been of the type covered and explained with solutions in the pages I had finished studying.  So I quickly scanned the previous dozen pages but I still couldn't find any clarity.  It makes me aware that these type of questions might be lurking for me as I progress further....yum yum:)

## #13 Help Me ! » If you know the sum of the factors of a number, what the number? » 2014-03-06 13:33:03

silverpuma
Replies: 3

back again for help.  A another question from my textbook that although I got the answer right by trying out different numbers but I'm sure there must be a easier/faster, formula way but I can't seem to find it in the previous teaching in the text book.

The question is....The sum of the factors of x is 18.  What is x?

I found the prime factors of 18: they are 2 x 3 x 3  But I could not see how this would help me.  And after a few runs trying different numbers I found that 10 with the factors of 1, 2, 5, 10 added up to 18.  So x = 10  But there has to be a more elegant way than trying numbers until one fits especially if the question was a larger number, for example say..... The sum of the factors of x is 511.  What is x?

That would take a lot of tests before the answer.  Probably the answer is sitting in front of me but.....I think the age is showing:  thanks guys...........

## #14 Re: Help Me ! » Help with this Prime factor sq root example » 2014-03-06 03:59:54

Thanks guys for the help and after my MIF reading last night and a period of head scratching my maths question became crystal clear and I'm happy to move on to the next page on my text book.  I really enjoy this when something is fuzzy and then all of a sudden it begins to make sense.

@bob bundy   The way my son's school works is that the students study Key stage 3 over yr 8-10.  Then the majority of the year will do their maths higher GCSE over 2 years (y11 - y12).  But some who show the ability and interest (so far my son is in this group) do this GCSE higher maths in 1 year instead of 2 , at the end of y11.  Then they do this additional/further maths exam at the end of y12 so they have 2 maths qualifications during this 2 year period,  where most have the normal 1 GCSE maths qualification over 2 years.  Then they begin the normal A-Level course over 2 years. For this the school uses the edexcel A-Level course C1 C2, C2, C4 M1 and S1.

Bob you said above...

"Did you mean GCSE then 1 year extra GCSE then 2 more years A level ?  What's to stop doing the extra concurrently with year 1 A level to short cut the process?"

I think the main thing is that since this additional/further 1 year maths qualification over 1 year is a bridge to A-Levels and include subjects that are in the first year A-Level so there would be too much overlap and double learning at the same time.  But that's just me thinking out loud.

Another question just popped into my mind:-)  When finding the prime factors of large number without a calculator I noticed that sometimes I would be unsure if a 3 or a 7 or a 11 for example would divide equally.  I know a even number will divide by 2 and 5 divide into numbers ending with 0 and 5 but is their shortcut ways to find if a 3,7,11,13 etc will divide other than doing the full division?  ....I appreciate all the help

## #15 Re: Help Me ! » Help with this Prime factor sq root example » 2014-03-05 09:25:32

thanks bobbym, things are becoming clearer.  I'll feast on the MIF page after supper.....yum yum.

This is completely unrelated to my question but I'm curious, my son can do his UK GCSE higher maths exam at the end of year 11 and then additional maths (the cces board is changing the name this year to Further maths) at the end of year 12 so if all goes well he will have 2 GCSE maths and then begin 2 years of A-Level maths.  The additional/further qualification is like a bridge between GCSE and A-Level and is via the ccea exam board.  Does the English set-up have an equivalent "in between" type qualification.

Course Content

The course is divided into two sections, namely Pure Mathematics and Mechanics and Statistics.  Topics covered in each section are detailed below.

Pure Mathematics     Mechanics and Statistics
Algebra                     Linear Motion
Matrices                     Summarising Data
Trigonometry             Newton's Law
Logarithms                     Time Series
Differentiation             Equilibrium and Motion
Integration                     Bivariate Analysis
Moments of Forces
Probability

Does edexcel or aqa etc have similar?

## #16 Help Me ! » Help with this Prime factor sq root example » 2014-03-05 07:54:38

silverpuma
Replies: 6

Hi all,  I need some hand holding.  I just finished the GCSE foundation text book all 600 pages and after doing 3 full previous exams under exam conditions, timed etc I managed an average of 97% so I have a reasonably good grasp of the basics.

I just started the higher text book and just on page 16 after some pages on powers, roots primes, factors, multiples and then HCF and LCF (using prime factors) I arrived at examples 24 and 25 (see image of actual textbook page) it seemed to just jump up a level in understanding and I do not understand what the end of example 23 means: "Therefore 21 is the smallest value which 55125 can be multiplied by to give a cube number"

I understood all that came before this but I'm confused as to how this relates or builds upon what I have already learned......probably my 1.5 brain cells overheating....:-)  Where on the MIF site could I get some info that would help me understand this question and example 24 and especially 25 better.  I want to know why this works etc....... thanks and sorry for not being the sharpest chisel in the box!!!

## #17 Re: Help Me ! » On a multi-part question when do you round to significant figure? » 2014-02-02 02:46:50

Thanks Bob for the great answer and all makes perfect sense.....I suppose in maths like a lot of things in life there is a certain amount of "common" sense to be applied as well:-)

## #18 Re: Help Me ! » On a multi-part question when do you round to significant figure? » 2014-02-01 15:30:53

thanks for the links bobbym its appreciated.....

## #19 Help Me ! » On a multi-part question when do you round to significant figure? » 2014-02-01 08:59:57

silverpuma
Replies: 5

Hi folks,  I have a question to do that has a few parts but it states the answer is given to 3 significant figures.  I can do all the calculations but am wondering about the 3 significant figures (which I understand how to do as well).  The answer must be given in m^2

I'm given a square lawn 30m x 60m and inside the square lawn are 4 round paved areas, 2 have dia of 1.9m, one a dia of 2.2m and one a dia of 0.9m.

Do I do all my working out of all the circle areas, adding them together and subtracting from the 180 (area of lawn) and only when I get that final figure of do I consider the 3 significant figures?

Its just for example the circle with a dia of 0.9m works out at

0.6361725124 m^2  as Im working through the question and the other circles do I need to use the 10 digits after the decimal point  or because I know I'm working towards 3 s.f. can I just use say 4 digits after the decimal point?

Hope Im making sense........thanks for your patience:)

## #20 Re: Help Me ! » Help with grasping better problems with negative nymbers » 2013-12-18 19:47:06

Bod, hope its OK to post a link but is this the book you mentioned?  Its just there seem to be so many variations to choose from I want to make sure I get the right one.

http://www.amazon.co.uk/GCSE-Mathematics-Edexcel-2010-Student/dp/1846900832

How do you post a live link here.  Usually I see a "link" button?

Thanks..................

## #21 Re: Help Me ! » Help with grasping better problems with negative nymbers » 2013-12-18 19:28:53

Thanks Bob for this info and recommendation and I think I'll buy myself a secondhand copy as a gift to myself for Christmas.  Some light bedtime reading...............is that sad or what......

## #22 Re: Help Me ! » Help with grasping better problems with negative nymbers » 2013-12-17 23:24:40

bobbym wrote:

Hi;

PS:  I love reading along side the forum and web is there a book on Learning maths you could recommend for me.

I have covered hundreds, sometimes emptying out massive shelves of books in the University library. I have never really found anything easier than the MIF pages right over here. I truly mean that. I suggest you keep going through them and copying them.

Books are fine but nothing beats the web for learning. If I would have had the internet and access to this forum when I was just starting out I would be much further along. That is not hype, I am serious. The opportunity to come in and ask a question and get an immediate answer is fantastic. I had to wait years before I found answers to many questions.

Try to go at your own pace. It is much better to know a handful of techniques or concepts thoroughly then to have a smattering of a lot of them.

I mean this genuinely and no false flattery the MIF site and this forum is my first place to call on when I want to learn a new section on my maths adventure.  I love the concise and clear teaching and as you mentioned the help on the forum only accentuate these positives.  There may be other more visually slick sites but the content is king in my book.

It amazes me sometimes how the obvious passes me by so often.  I discover my blind-spots continuously....! Why didn't I think of copying and printing out the material on the MIF site as you say? Ebay here I come for a batch of cheap ink cartridges......he he.

## #23 Re: Help Me ! » Help with grasping better problems with negative nymbers » 2013-12-17 22:26:13

Ahhhh the.... "brackets"...... thanks guys!  This makes all much clearer.  I don't like to move on to another level or section if I'm not comfortable with a question so this is great to receive the help .  Simple when you know how ...:-)

@bobbym I have found probabilities perhaps the most difficult to get my head around.  But the individual part I've found the hardest so far to feel I grasped fully was the "why does multiplying two negs make a pos".  I could follow the rules on the same and different signs ok so could get the right answer (most of the time...!!) but understanding "why" this was so, I found difficult for a while.  The balloons example on the mathsidfun site and the:  quote:

Example: You owe 3 people \$5 each. So you are "Negative 15" (3 × -\$5 = -\$15).
They then say "we like you so much we forgive the debt" ... you have just had 3 subtractions of -5, so it is like you have added \$15 (-3 × -\$5 = +\$15)."

Was the help I needed to "get" this infused in my bones.......................thanks again guys

PS:  I love reading along side the forum and web is there a book on Learning maths you could recommend for me.  I'm basically learning with my son as he goes through his Maths lessons trying to keep a little ahead so I can help as best I can.  He is year 9 so 2nd year at grammer school and he and I need to arrive at as high a GCSE standard as we can.  I mentioned before that his teacher is first class and gives out a small booklet for each term with examples etc that is very well produced and a picture of concise information but I'd like a book to supplement this as I enjoy the learning process.

## #24 Help Me ! » Help with grasping better problems with negative nymbers » 2013-12-17 19:46:37

silverpuma
Replies: 10

Hi all,  I'm at Probabilities in my journey and have understood this section on Mathsisfun  http://www.mathsisfun.com/multiplying-negatives.html  So I have a reasonably good grasp of things so far.  But one aspect that I can't see a section on in Mathsidfun and this idea is hurting my wee 1.5 cell brains is things like:

6^2 = 6 x 6= 36

(-6)^2 = -6 x (-6) = 36 (the 2 - negs make a pos)

These 2 examples above I can understand but the next 2 I'm not as clear on, especially the next one.

-6^2 = -36 (I thought that would be -6 x -6 = 36)

(-6)^2 = 36

I know this question is a bit confused but that's because I am a bit confused ....:-)  I really need a link to a page that will spell this out for me so I can understand "why" 3rd above is -36 and not 36 as I would have thought.........................thanks for the hand holding and patience!

PS how can I type x squared instead of using the ^ symbol.  I notice often you guys used a grayed out image type of text?

## #25 Re: Help Me ! » Bob and others could you take a look at this question » 2013-12-10 07:32:30

anonimnystefy wrote:

It will be okay as long as there are no harsh words. It's better to do it now then to let all the students including your son learn math wrong.

Thanks again guys and.....  there will be no harsh words.  I'm really thankful for my son's teacher and I know he want's the best for him and has a very good reputation for producing accomplished maths students.  This is just a couple of slip-ups i think due to pressure of work.  Also this was homework and I suppose I would be more concerned if it was exams or structured tests etc.