A letter to the Sheffield Star
As someone who teaches maths for a living it saddens me when I see mathematical errors in your paper.
In a letter about Council Tax increases (21.2.18) Ron Sanderson claimed that last year’s 5.99% rise combined with this year’s 4.99% rise made a total increase of 10.98%. He has added the percentages, ignoring the fact that this year’s increase is 4.99% more than the new total for last year.
For every 100p you paid in Council Tax in 2016, you paid 100 x 1.0599 in 2017.
In 2018 you will pay 100 x 1.0599 x 1.0499 which equals 111.28p or an increase of 11.28%
Understanding percentages is vital when working out things like Council Tax rises, pay claims, credit agreements or interest earnt on investments. People who don’t understand percentages and APR’s are much more likely to be ripped off. If you need help with maths visit my website at www.mathswithgraham.org.uk where you will find free activities, some with a Sheffield theme such as the Sheaf Valley Maths Trail, to help people of all levels, from the very basic up to Higher GCSE.
Maths with Graham
This exercise involves reading and analysing data from charts, calculating averages and percentages and estimating length. It will also help you with the Driving Theory Test and hopefully help you to stay safe when you are driving.
There is an interactive version here and a worksheet version here.
Can you correctly answer the questions about this graph?
There are two extra questions on the worksheet which are also below.
- Draw a suitable chart to display this data.
- Write two interesting facts that the graph shows.
In May 2015 the United Kingdom went to the polls. A Conservative Government was elected. The UK uses the “first past the post” electoral system. The country is divided into 650 constituencies. The candidate with the most votes from each constituency is elected.
Most other countries in Europe use various forms of proportional representation. This means that the number of MP’s for each party would be proportional to the number of votes that were cast for them. (There are many different forms of PR, but in this exercise, to keep it simple we are going to work out the number of MPs by dividing the vote for each party by the total vote and then multiplying by 650, which is the total number of MP’s in the House of Commons. )
First fill in the missing numbers in this table. You will need a calculator. Remember that to round to two decimal places you need to look at the 3rd decimal place. If this is 5 or more round the 2nd decimal place up. If it is less than 5 then ignore it. eg 34.349239=34.35 to 2dp. 2.983432909=2.98 to 2 dp.
If you got the first exercise correct I want you to illustrate your results with two pie charts. Use this table to work out the degrees for each party. You can draw them in excel or with a protractor and pencil.
If you would rather do this exercise using a worksheet download here.
This is one in a large series of short videos from NCETM showing how people use maths at work. See the others here.
Here is a great phone app that will help you with your arithmetic so you don’t need to be afraid when you are faced with that non-calculator exam. It’s called Maths Tricks and shows you lots of short cuts to performing calculations and gives you endless practice to improve your speed and accuracy. Best of all it’s free!
You can find it on Google Play. I am recommending this because it is good, not because I have any connection to the app.
This interactive worksheet will help you get to grips with simple and compound interest.
Maths 4 us have produced a new free on-line course about Numbers in our Food.
Obesity is still increasing in South Yorkshire. Do the maths, then go and get some exercise!
In May 2013 global levels of carbon dioxide in the atmosphere passed the milestone of 400 parts per million. This exercise will challenge your maths and help you understand why this is so important.
Watch the video on Income Inequality then see if you can answer the questions.
Do you understand those letters that come through the door offering you a credit card? Have a go at this exercise to find out more.
Here is a worksheet version.
(I have used Sainsbury’s Bank as an example of a typical credit card provider- this exercise does not insinuate that Sainsbury’s Bank is any worse than other credit card providers.)
Many people on a low income are not able to open a bank account. If they need to borrow money they can be offered loans with massive rates of interest. This exercise looks at how to calculate interest rates and compares different ways of borrowing money.
The video mentions two businesses in particular. Wonga.com and Quick Quid both charge interest rates in excess of 2000%. Do you know of higher rates of interest? Please comment below to name and shame the loan sharks!
The same exercise is here in worksheet format.
The Joseph Rowntree Foundation research into the minimum income standards for the UK. The Minimum Income Standard for the UK shows how much money people need, so that they can buy things that members of the public think that everyone in the UK should be able to afford.
- Figures are based on public views about a minimum standard that nobody should fall below.
- It does not show you what you require to meet all your individual needs, and is not suitable for use as a personal budgeting tool.
By entering a few details about your circumstances you can compare your income with the MIS, and see how this is made up. For instance my children are now all grown up and have left home, so I live with my wife. When I have entered details about my rent/mortgage. gas/electric/water bills etc it tells me the minimum income I require is £23,099. They break this down into how much I need for food, alcohol. council tax, clothing etc. It makes very interesting reading!
Go to http://www.minimumincome.org.uk/ and enter your details to see what it suggests for your household.
Try this exercise to find out about a single persons minimum income. It will also help you to calculate percentages.