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#1 Re: Help Me ! » Mandy Jane's Corner » 2014-08-29 04:12:01






















I have sent you a spreadsheet of this, but it went through to your mobile. I will try sending it again if you like, but you can always just use the post above. Are you okay ?

#3 Re: Help Me ! » Mandy Jane's Corner » 2014-08-27 20:37:50

Here is another set of fractions, decimals and percentages, I will send you a spreadsheet version of these:

Fraction    Decimal    Percentage
   1/5         
   1/8         
   3/20        
   2/25        
                 0.5   
                 0.35   
                 0.75   
                                 55%
                                 95%
                                 24%

#4 Re: Help Me ! » Mandy Jane's Corner » 2014-08-27 19:36:31

Fraction    Decimal    Percentage
   4/5         0.8            80.00%
   1/12       0.0833        8.33%
   6/7         0.8571      85.71%
   1/3         0.3333      33.33%
  13/20      0.65          65.00%
   4/25       0.16          16.00%
  11/20      0.55          55.00%
   3/5         0.6           60.00%
   2/5         0.4           40.00%
   1/5         0.2           20.00%
   4/5         0.8           80.00%

#5 Re: Help Me ! » Mandy Jane's Corner » 2014-08-27 19:24:49

Fraction    Decimal    Percentage
   1/2           0.5             50%
   1/4           0.25           25%
   2/5           0.4             40%
   3/20         0.15           15%
   9/20         0.45           45%
   3/4           0.75           75%
   5/8           0.625       62.50%
   3/8           0.375       37.50%
  49/50        0.98           98%
   7/40         0.175       17.50%
   3/8           0.375       37.50%
   3/5           0.6             60%
  11/25        0.44           44%
   3/25         0.12           12%
     1                1           100%

#6 Re: Help Me ! » Mandy Jane's Corner » 2014-08-26 23:04:13

Since Bob joined in with this you have improved, but I don't want to get too mad with excitement that you could pass GCSE. I am hopeful that in terms of everyday maths you are doing well and better than before. One thing we did think about is that maybe you should avoid doing the full GCSE and just try to benefit from the forum engagement to get you improved. To get a 'C' at GCSE for you is a tall order. I personally would recommend going full steam ahead towards learning basic maths.

#7 Re: Help Me ! » Mandy Jane's Corner » 2014-08-26 22:23:09

Just for the record there was one silly mistake in my answers that I sent to you where I had made a mistake with 0.12 and converting this to a fraction.
The correct answer is in fact (3/25) as a fraction and not (6/25) so sorry about that.
The working for this might go as follows:
0.12 = 12 /100
12 /100 = 6 / 50
6 / 50 = 3 / 25
I wrote those out in a hurry.

#8 Re: Help Me ! » Mandy Jane's Corner » 2014-08-25 01:06:24

The latest set of questions are as follows:

Fraction             Decimal               Percentage

4/5                    ---------               -----------

1/12                  ---------               -----------

6/7                    ---------               -----------

1/3                    ---------               -----------

----------              0.65                  -----------

----------              0.16                  -----------

----------              0.55                  -----------

----------            ----------                 60%

----------            ----------                 40%

----------            ----------                 20%

----------            ----------                 80%

My apologies by the way about 1/12, 6/7 and 1/3
I realise that these need rounding.
I should try to round them to 2 decimal places if you can.
See if you can format the text in the spreadsheet,
but don't worry if you can't.

#9 Re: Help Me ! » Mandy Jane's Corner » 2014-08-25 00:11:38

I have sent an email reply you with some marking. You are doing very well. Be careful about the fact that you tend to multiply by 1000 rather than 100 for some of the percentages. If you have something like 0.625 then the percentage is 62.5% not 625% for instance. We need to build up your intuition so that you know when you have made this mistake. However very good progress and good use of technology there with the spreadsheet. A lot of maths can be done on spreadsheets.

#10 Re: Help Me ! » Mandy Jane's Corner » 2014-08-24 22:36:07

I can't insert the fraction, decimal and percentage work as an image however here is a plain text version of the latest set of practice questions for you. Each series of minus signs represents an item for you to try and work out.

Fraction      Decimal          Percentage

1/2            ----------          ------------

-------         0.25               ------------

3/20          ----------          ------------

--------        0.45                    75%

5/8            -----------         ------------

--------        0.375             ------------

--------       -----------              98%

7/40          ------------        ------------

-------         0.675              ------------

-------        ------------             60%

22/50        ------------        ------------

-------         0.12                ------------

-------        ------------           100%

#11 Re: Help Me ! » Mandy Jane's Corner » 2014-08-06 22:44:20

Question (1) Consider the following 10 symbols : XXXOOOOOOO
There are 3 Xs and 7 Os
What percentage are Xs ?
What percentage are Os ?
Draw a diagram with 100 items if it helps.

Question (2) Consider the following diagram:
OOOOOXXXXX
OOOOOXXXXX
OOOOOXXXXX
OOOOOXXXXX
OOOOOXXXXX
There are 50 symbols in total. Imagine that there were twice as many and in the same proportion.
What percentage are Os ?
What percentage are Xs ?

Question (3)
Draw a diagram that represents 25% Xs and 75% Os
The total number of symbols must be 8.

Question (4)
Draw a diagram in which 40% are Xs and 60% are Os.
The total number of symbols must be 20.

I will send you an email copy of that lot just in case it is easier to see in an email.

#12 Re: Help Me ! » Mandy Jane's Corner » 2014-08-06 22:30:44

Okay Mandy I will make up some new questions. The first one can be the one in post 1446. I may need half an hour at least to make up some questions.

#13 Re: Help Me ! » Mandy Jane's Corner » 2014-08-06 22:21:09

How about this for instance XXXOOOOOOO

There are 3 Xs and 7 Os there.

What percentage are Xs and what percentage are Os ?

#14 Re: Help Me ! » Mandy Jane's Corner » 2014-08-06 22:19:32

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.

#15 Re: Help Me ! » Mandy Jane's Corner » 2014-08-06 22:04:59

I am going to class questions 1 and 2 as correct with full marks.
With question 3 you did not manage to end up with a representation so no marks for that I'm afraid.
With question 4 you would only be right if there were another 96 symbols knocking about somewhere so I will class that as a good effort, but wrong.
So 2 out of 4 correct.

#16 Re: Help Me ! » Mandy Jane's Corner » 2014-08-06 22:00:53

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

#17 Re: Help Me ! » Mandy Jane's Corner » 2014-08-06 21:52:29

Let us have a look at question 4 and think about it in a different way:

We had 4 symbols in total namely:

XX
OO

Now let us imagine that we repeat those four items until there are 100 symbols:

XXOO XXOO XX
OO XXOO XXOO
XXOO XXOO XX
OO XXOO XXOO
XXOO XXOO XX
OO XXOO XXOO
XXOO XXOO XX
OO XXOO XXOO
XX OOXX OOXX
OO XXOO XXOO

There are 100 symbols altogether.

There are 25 pairs of Xs so there are 50 Xs.
There are 25 pairs of Os so there are 50 Os.

I conclude that 50% are Xs and 50% are Os.

#18 Re: Help Me ! » Mandy Jane's Corner » 2014-07-28 21:13:31

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

#19 Re: Help Me ! » Mandy Jane's Corner » 2014-07-28 21:11:46

You are getting warmer but that still does not work.
The total of all of them is 12 so the thing on the lower part of the fraction has to be the amount that it is out of.

#20 Re: Help Me ! » Mandy Jane's Corner » 2014-07-28 21:10:10

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.

#21 Re: Help Me ! » Mandy Jane's Corner » 2014-07-28 06:23:29

Let's revise percentages. Don't worry about those above questions Mandy.

Here are a few examples of O and X percentages where the number of letters rather than the area is of concern.
Since the letters have different widths I will stick to the same length of row in each case in terms of the letters.

This is a case of 10% Xs and 90% O

XXXXXXXXXX
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO

Of course since percentages are a measure of proportion there don't have to be 100 items as such:

X
OOOOOOOOO

If you have the above situation then there are 9 Os and 1X there so the proportion of Xs is still 10%
and the proportion of Os is still 90%

If you have this:
OO
XX

The proportions are 50% X and 50% O

You could expand this to:
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
OOOOOOOOOO
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX

So there are 5 lots of ten of each. So there are 50 Os and 50 Xs meaning 50% O and 50% X.
I will leave it there for now. You have some reading to catch up on. I will leave you to it.

One question for you to try:
What are the percentages in this case:
OOO
XXX
XXX
XXX

What percentage of those are Os ? What percentage of those are Xs ?

EDIT: Another hint:

OOOOOOOOOO
OOOOOOOOOO
OOOOOXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX

#22 Re: Help Me ! » Mandy Jane's Corner » 2014-07-26 08:12:35

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


#23 Re: Help Me ! » Mandy Jane's Corner » 2014-07-25 07:43:45

Okay I agree let us leave it a day.

EDIT:

Answer to Q3 for the record: 212.62125/500 = 0.4252425
Multiply by 100 to convert to a percentage: 42.52425% which rounds to 43%


Since Q4 is slightly easier than Q3 and similar you might like to attempt Q4.
I will leave it up to you. Take your time and try to get the answer correct.

#25 Re: Help Me ! » Mandy Jane's Corner » 2014-07-25 04:56:44

Yes that's correct.




Hint: What is the numerator and what is the denominator? What has to be divided by what?
Do you have to multiply by 100 for any reason?

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