SO16_Saint Posted 15 December, 2012 Share Posted 15 December, 2012 I need to explain that 0.75 is 75% and also 3/4. 1/2 = 0.5 = 50% Why/ how do I explain that 3/4 = 0.75 = 75% Link to comment Share on other sites More sharing options...
colehillsaint Posted 15 December, 2012 Share Posted 15 December, 2012 3 divided by 4 is 0.75 so that isn't a difficult concept. Link to comment Share on other sites More sharing options...
SO16_Saint Posted 15 December, 2012 Author Share Posted 15 December, 2012 3 divided by 4 is 0.75 so that isn't a difficult concept. I don't think I'm getting this over well. How do I explain to a 10 yo that 0.75 = 3/4 . I can explain why 0.5 = 1/2 but how do you explain that 0.75 becomes 3/4? Link to comment Share on other sites More sharing options...
Deano6 Posted 15 December, 2012 Share Posted 15 December, 2012 I don't think I'm getting this over well. How do I explain to a 10 yo that 0.75 = 3/4 . I can explain why 0.5 = 1/2 but how do you explain that 0.75 becomes 3/4? How are you explaining that 0.5=1/2, and why does the concept not then work for 3/4? Link to comment Share on other sites More sharing options...
SO16_Saint Posted 15 December, 2012 Author Share Posted 15 December, 2012 She just knew that 0.5=1/2. Link to comment Share on other sites More sharing options...
colehillsaint Posted 15 December, 2012 Share Posted 15 December, 2012 A fraction, i.e 3/4, is simply a way of writing the answer to the question; what is three divided by four? If you get a calculator and input 3 divided by 4, the answer will be 0.75 Link to comment Share on other sites More sharing options...
SO16_Saint Posted 15 December, 2012 Author Share Posted 15 December, 2012 A fraction, i.e 3/4, is simply a way of writing the answer to the question; what is three divided by four? If you get a calculator and input 3 divided by 4, the answer will be 0.75 But if you have "put 0.75 as a fraction" how do you know/explain this as being 3/4?? Link to comment Share on other sites More sharing options...
bridge too far Posted 15 December, 2012 Share Posted 15 December, 2012 If you've successfully explained that 1/2 is 0.5 then try demonstrating that 1/2 of 1/2 = 1/4 therefore 0.25 and then lead on to 3 x 1/4 = 0.75? Link to comment Share on other sites More sharing options...
Horley CTFC Saint Posted 15 December, 2012 Share Posted 15 December, 2012 .25 + .25 + .25 + .25 = 1 1/4 + 1/4 + 1/4 + 1/4 = 1 Link to comment Share on other sites More sharing options...
SO16_Saint Posted 15 December, 2012 Author Share Posted 15 December, 2012 Ok... by doing another question furher on, we have come up with: 75%=75/100= 15\20 (5 goes into both) 3/4 (3 times and 4 times respectively) Link to comment Share on other sites More sharing options...
colehillsaint Posted 15 December, 2012 Share Posted 15 December, 2012 Start with 0.75/1 A fraction has to have whole numbers. Times 0.75 by 1 then 2 then 3 etc. When you try timesing by 4 you finally get a whole number - 0.75 x 4 = 3 So the top of fraction now equals 3, but you have to times the bottom by the same amount to keep the fraction the same; 4 x 1 = 4 Hey presto 0.75 = 0.75/1 = 3/4 Link to comment Share on other sites More sharing options...
the stain Posted 15 December, 2012 Share Posted 15 December, 2012 Excuse my ignorance, but how is everyone so sure that 0.5 = 1/2? Link to comment Share on other sites More sharing options...
Whitey Grandad Posted 15 December, 2012 Share Posted 15 December, 2012 Excuse my ignorance, but how is everyone so sure that 0.5 = 1/2? Because twice 0.5 is one. Write 0.5 as 0.5/1 Multiply top and bottom by 2 ...gives 1/2 Link to comment Share on other sites More sharing options...
Halo Stickman Posted 15 December, 2012 Share Posted 15 December, 2012 There are 3 types of people in the world: those that are good at maths and those that aren't Link to comment Share on other sites More sharing options...
Draino76 Posted 15 December, 2012 Share Posted 15 December, 2012 I would use a pizza. Link to comment Share on other sites More sharing options...
SO16_Saint Posted 15 December, 2012 Author Share Posted 15 December, 2012 There are 3 types of people in the world: those that are good at maths and those that aren't Ha! This I like!! Link to comment Share on other sites More sharing options...
Ken Tone Posted 15 December, 2012 Share Posted 15 December, 2012 Does the 10year old understand that 0.5 = 5/10 ? Because if so , it is a fairy easy step to 0.75 = 75/100, and it easy to demonstrate that 75/100 = 3/4, even if you have to resort to drawing a square 10by 10 and colouring in 75 of them. Link to comment Share on other sites More sharing options...
Doctoroncall Posted 15 December, 2012 Share Posted 15 December, 2012 I would use a pizza. This works well with my kids for fractions and percentages. Link to comment Share on other sites More sharing options...
Micky Posted 16 December, 2012 Share Posted 16 December, 2012 I would use a pizza. Strangely this is probably the best advice on here. I have just done exactly the same with my 9 year old son. The maths are not the important thing at the moment - it's simply understanding the relationship between decimals, percentages and fractions. I struggled initially to explain the mathematical workings - without too much success. Then I used a pizza slices. Link to comment Share on other sites More sharing options...
View From The Top Posted 16 December, 2012 Share Posted 16 December, 2012 Checkout http://www.primaryresources.co.uk. You should find plenty on there to help. Sent from my GT-P3110 using Tapatalk 2 Link to comment Share on other sites More sharing options...
the stain Posted 16 December, 2012 Share Posted 16 December, 2012 Then I used a pizza slices. Are you teaching him how to speak English with an Italian accent as well? Link to comment Share on other sites More sharing options...
norwaysaint Posted 16 December, 2012 Share Posted 16 December, 2012 If you really need to explain this, you can draw a large circle or square, dividing it into 4 sections. I each you draw 25 people/dots/whatever. It will then be clear that each quarter is 24 and three quarters are 75. In other words 75 hundredths is the same as three quarters. then explain that the decimal notation of 75 hundredths is 0.75. Honestly, though, I don't feel it's entirely necessary at first. I would say that it's enough to know those three decimals correspond to those fractions and the understanding of decimals can grow out from there, rather than expecting them to understand the concept of decimals first. Link to comment Share on other sites More sharing options...
the stain Posted 16 December, 2012 Share Posted 16 December, 2012 If you really need to explain this, you can draw a large circle or square, dividing it into 4 sections. I each you draw 25 people/dots/whatever. It will then be clear that each quarter is 24 and three quarters are 75. In other words 75 hundredths is the same as three quarters. then explain that the decimal notation of 75 hundredths is 0.75. Honestly, though, I don't feel it's entirely necessary at first. I would say that it's enough to know those three decimals correspond to those fractions and the understanding of decimals can grow out from there, rather than expecting them to understand the concept of decimals first. Cheers ns, you seem to know what youre talking about. How large should the circle be? Can you give some context? Do the 4 sections have to be the same size? Would it be ok to draw 25 dogs and do all the dogs have to look the same? Thanks in advance. Link to comment Share on other sites More sharing options...
Smirking_Saint Posted 16 December, 2012 Share Posted 16 December, 2012 You need to explain that we can express quantities as either a fraction or a number. Perhaps get 10 sweets or something and arrange into four quarters. i.e four sweets. Prove that the whole amount is 100%, 4/4ths and so 1. If you take one sweet away you are left with 3/4ths, or 75% which can also be express as 0.75 as you now you have removed a part of the original whole unit and are expressing that missing fraction as a decimal. What is it the ten year old is struggling with ? The concept of fractions ? Percentages or decimals ? Link to comment Share on other sites More sharing options...
Whitey Grandad Posted 16 December, 2012 Share Posted 16 December, 2012 Can you explain that decimals are in fact fractions with a denominator of 10, 100 etc.? Link to comment Share on other sites More sharing options...
ericofarabia Posted 16 December, 2012 Share Posted 16 December, 2012 Is her maths teacher at school a skate? In a world where 180 million = 4000 or whatever, numbers become meaningless. Link to comment Share on other sites More sharing options...
dubai_phil Posted 16 December, 2012 Share Posted 16 December, 2012 Deffo agree with EoA. You are asking these questions on totally the wrong forum try this one http://www.pompeyonline.com/forums/index.php?login/ they are the maths geniuses Link to comment Share on other sites More sharing options...
SO16_Saint Posted 16 December, 2012 Author Share Posted 16 December, 2012 Thanks for all the replies. Got it sorted in the end. Thinking it through, it's easy to see how a 10yo is confused when a quarter is 1/4, three quarters is 3/4 but two quarters ( a half ) is 1/2 - "why isn't it 2/4". Damn maths!! Link to comment Share on other sites More sharing options...
Whitey Grandad Posted 16 December, 2012 Share Posted 16 December, 2012 Thanks for all the replies. Got it sorted in the end. Thinking it through, it's easy to see how a 10yo is confused when a quarter is 1/4, three quarters is 3/4 but two quarters ( a half ) is 1/2 - "why isn't it 2/4". Damn maths!! It is 2/4 but divide top and bottom by 2 to make it simpler. Another question- should vulgar fractions be taught to young children? Link to comment Share on other sites More sharing options...
the stain Posted 16 December, 2012 Share Posted 16 December, 2012 It might be vulgar to you, mate, but some of us value education. Link to comment Share on other sites More sharing options...
sandwichsaint Posted 16 December, 2012 Share Posted 16 December, 2012 You could do it with money. Work around a pound being 'one', the pennies are hundreths (100 x 1p =£1) 1p = 1%, 10p+10% etc.. Work around this to get the idea 50p = 50% 50p add 50p =£1 (50p is half of a pound, a half is one part out of 2, written as 1/2, 50p and 50p = a whole one, 1/2 add 1/2 equals 2/2 etc. The equalvalencies are prob not that important at this stage, more important to understand decimals/fractions/percentages as three seperate entities - once child has an understanding of all three the links/conversions will be fairly self explanatory. Link to comment Share on other sites More sharing options...
hamster Posted 16 December, 2012 Share Posted 16 December, 2012 Ask her 'add .25 to .75' 'equals 1.00 yes?' 'so how many .25's are thee in .75?' '3, yes?' 'So, that tells us that .25 is the same as1/3. Tara. Very convoluted, I know but I have that weird kind if learning style. Hence, I was a very tough pupil for your run of the mill comprehensive teacher, leading to my poor educational level. My explanation of my 'learning style' is to emphasise the key to being a good teacher for you. You must adapt your 'teaching style' to HER 'learning style' Link to comment Share on other sites More sharing options...
Hamilton Saint Posted 16 December, 2012 Share Posted 16 December, 2012 (edited) The key is equivalent fractions. 1) Equivalent fractions: multiply both terms (numerator and denominator) of the fraction 3/4 by 25 and you get 75/100. [And by the reverse process, divide both terms of the fraction 75/100 by 25 and you get the equivalent fraction of 3/4.] 2) Decimal numbers are decimal fractions; so 0.75 is the same as 75/100. 3) Percentages (by definition) are out of 100; so 75/100 is the same as 75% (75 out of 100). Edited 16 December, 2012 by Hamilton Saint Link to comment Share on other sites More sharing options...
sandwichsaint Posted 16 December, 2012 Share Posted 16 December, 2012 The key is equivalent fractions. 1) Equivalent fractions: multiply both terms (numerator and denominator) of the fraction 3/4 by 25 and you get 75/100. [And by the reverse process, divide both terms of the fraction 75/100 by 25 and you get the equivalent fraction of 3/4.] 2) Decimal numbers are decimal fractions; so 0.75 is the same as 75/100. 3) Percentages (by definition) are out of 100; so 75/100 is the same as 75% (75 out of 100). Bit abstract for a 10 year-old? Link to comment Share on other sites More sharing options...
the stain Posted 16 December, 2012 Share Posted 16 December, 2012 I think Hamilton Saint is an older gentleman Link to comment Share on other sites More sharing options...
Bearsy Posted 16 December, 2012 Share Posted 16 December, 2012 Give her 3/4 of her pocket money. She'll soon figure it out. Link to comment Share on other sites More sharing options...
angelman Posted 16 December, 2012 Share Posted 16 December, 2012 Multiply the top and bottom part of the fraction 3/4 by 25 and that will give you 75/100. Same thing except 3/4 is the simplest form when reducing fractions. Link to comment Share on other sites More sharing options...
PhilippineSaint Posted 17 December, 2012 Share Posted 17 December, 2012 completely confuse her by doing it using old money pound shillings and pence, then give her a thruppenny bit for her pocket money Link to comment Share on other sites More sharing options...
SO16_Saint Posted 17 December, 2012 Author Share Posted 17 December, 2012 Multiply the top and bottom part of the fraction 3/4 by 25 and that will give you 75/100. Same thing except 3/4 is the simplest form when reducing fractions. But that's part of the original question: How would she know that she would have to (in reverse, to get to 3/4) divide 75 by 25 and 100 by 25? Link to comment Share on other sites More sharing options...
Hamilton Saint Posted 17 December, 2012 Share Posted 17 December, 2012 I think Hamilton Saint is an older gentleman Nice! I teach this stuff to 12 year olds every year. Not too much more advanced for a smart 10 year-old. Link to comment Share on other sites More sharing options...
Hokie Posted 17 December, 2012 Share Posted 17 December, 2012 There are 3 types of people in the world: those that are good at maths and those that aren't I think actually there are 10 types of people in this word. Those that read binary and those that don't. Link to comment Share on other sites More sharing options...
Hamilton Saint Posted 17 December, 2012 Share Posted 17 December, 2012 Bit abstract for a 10 year-old? The OP did not mention having to teach this to a ten-year old. Link to comment Share on other sites More sharing options...
Ruffo Posted 28 December, 2012 Share Posted 28 December, 2012 Cut an orange onto quarters. This has the added value of giving her healthy food as well Link to comment Share on other sites More sharing options...
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