Math Is Fun Forum

I think that you have made a good effort with your answer especially questions 1 and 2, but maybe you got a bit tired towards the end and didn't do so well with questions 3 and 4.
The point is: Do you now understand percentages or do we need to give you some more questions to test your understanding? I would say that we do.

Question 3 was probably the most tricky for you,
but if you think about it if you have
"Using only 4 symbols in total represent 25% Xs and 75% Os"
then we want to end up with 4 symbols in total.

So what is 25% of 4 items? Well the answer is 0.25 x 4 = 1
So we have only 1 X

Now what is 75% of 4 items? Well the answer is 0.75 x 4 = 3
So we have only 3 Os

So the answer is XOOO

The answer obtained by 3/9 would be 33.333.... % which is not right.

The denominator (bottom of the fraction) is the whole of them.
The numerator (top of fraction) is the "partial bit" of the proportion in each case.

Try again ?

Reminder of the question:

Let us call this Question (1):

What are the percentages in this case:
OOO
XXX
XXX
XXX
What percentage of those are Os ? What percentage of those are Xs ?

ANSWER: 25% are Os and 75% are Xs.
I was wanting to see something like this:
total number of items = 12
3/12 = 0.25
9/12 = 0.75
0.25 = 25%
0.75 = 75%

EDIT: Please refer back to post number #1429 at the end of the post.

Another question:

Let us call this Question (2):

What percentage of these are Xs ?

XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO

Each row has exactly ten items in and the total is 100.

ANSWER:
Since the total is already 100 by inspection 30% are Xs and 70% are Os

Here are four questions on percentages for you:
Question (1)
Using 100 symbols in total which are either Xs or Os represent the percentage 40% Xs and 60% Os

Question (2)
What are the percentages of Xs and Os in this diagram?
XXXXXXXXXX
XXXXXXXXXX
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO

Question (3)
Using only 4 symbols in total represent 25% Xs and 75% Os

Question (4)
What percentages of Xs and Os are represented by this diagram?
XX
OO

3% and 9% cannot be correct because the total of these two percentages is 12% and the two should add up to a whole namely 100%.
You could try expressing it as a fraction first that would be my method as well.

Mandy. Are you okay? Are you still continuing this?
Perhaps continue on Monday?

EDIT:

Consider a series of Os and Xs:

OOOOOOOOOO
OOOOOOOOOO
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX

Each row has 10 of the letter. Two fifths of these are Os and three fifths are Xs.
Imagine that there were two lots of that ie:

OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX

Out of 100 there are 40 Os and 60 Xs. So as a percentage there are 40% Os and 60% Xs.
You could do 2/5 = 0.40     then x 100 -> 40 %
and then 3/5 = 0.6       then x 100 -> 60 %

Now try answering Q4 with that method and round the answer off.

Okay I will reveal the answer to Q4:

I am getting: 9/29 = 0.31034... = 31.034...%
Rounded to the nearest percentage 31%

I am getting 7.5 / 29 = 0.258620..... = 26% rounded to the nearest percentage.

I will go through the other questions for completeness....
I apologise in advance if there are any mistakes.

The rate part of the question involves a cost of £3 per cubic metre and 120 cubic metres used.
So we do: £3 x 120 = £360
The standing charge added on is £100 regardless of other costs so:
£360 + £100 = £460
Then an allowance for VAT at 20% has to be made so:
£460 x 1.20 = £552

First observe that 13000 kWh has been used and divide by 1000.
This is because the rate is 47.50 per 1000 kWh.
So we do £47.50 x 13000 / 1000 = £617.50
Then add the yearly standing charge of 150:
£617.50 + £150 = £767.50
Then add 20% VAT:
£767.50 x 1.2 = £921

I am getting (37 x £7) + ( 2 x £9 ) = £277

I am getting £259 x 4 = £1036

£277 x 48 = £13296 for the amount excluding holiday pay
£13296 + £1036 = £14332

£4332 is taxable

£4332 x 0.2 = £866.40

Yes that is correct.

Hint: First work out the total amount of soft margarine then convert it into grams.
There was an amount of 6 ounces and 1.5 ounces to add together.

Hi Mandy. What topic of maths would you like help with? The maths above may be too challenging for you so shall we do some easier maths instead, but can you give me an idea of what chapter, topic or area you would like help with?

EDIT: I will probably go through some of those questions, but it is a good idea to try some yourself before someone gives away all the answers and makes it too easy.

Define the problem well and the meaning of things to avoid ambiguarity, make sure you have understood it correctly. Proofs are not always essential, but in practice courses will expect you to be able to prove things in maths so yes you do have to be able to prove things and it can help your understanding if you do prove them at some level at least. In practice exercises are essential because you need your brain to get the benefit of the exercise and it helps with understanding of any piece of maths to do some kind of exercise or exercises on the thing. Being a spectator and watching maths is not usually very good for learning it. It is rather like a sport - you have to do it in order to get better etc...

Hi Mandy. Happy birthday !

According to wikipedia dyscalculia is:
"difficulty in learning or comprehending arithmetic, such as difficulty in understanding numbers, learning how to manipulate numbers, and learning maths facts...."
whereas dyslexia is:
"characterized by difficulty with learning to read fluently and with accurate comprehension despite normal intelligence. This includes difficulty with phonological awareness, phonological decoding, processing speed, orthographic coding, auditory short-term memory, language skills/verbal comprehension, and/or rapid naming"

Therefore my conclusion is if you are finding the maths difficult to read and interpret then it is dyslexia (if either).
However if it is the understanding of numbers and how to manipulate them then if either it is dyscalculia.

As for learning maths I agree with what Agnishom was saying about being determined to succeed.
It is important to stay motivated if you are trying to learn something.
Let us work on the assumption that it is 'dyslexia' that you have. You might of course have a bit of both.
Whatever you do (if you want my advice) don't waste any money on the issue.

Hi Mandy. I have sent you an email about that one ....