# What use is maths?
You may wonder what connects the maths you do in school to the real world. Will you ever have to solve an equation or find an angle outside your classroom? Maths is very useful and is everywhere in everyday life. You might not think of buying sweets as algebra or consider the maths that went into designing your favourite computer game. However, maths is everywhere and what you learn in school will be very important for your future.
### Shaping up
You'll have studied shapes and space, which is the oldest branch of maths. The Greeks were able to calculate the radius of the Earth (which they knew was round!) using the same techniques you are now learning. Later on, trigonometry helped to put men on the moon. In the everyday world, the ideas in space and geometry are used in computer graphics, to make sense of medical scans and in designing haircuts, among many other things.
### Thinking in numbers
Arithmetic crops up a lot in daily life. For example, working out the dose of medicine to give your dog and if your pocket money will last for the whole week. You may often have a calculator around to help with this, but if you hit the wrong button, things can go very wrong. Being able to do mental arithmetichelps you spot if a number looks wrong - it's like having a safety net to catch you if you make a mistake.
### Lies, damned lies
Newspapers and TV news are full of statistics, used to make all kinds of arguments. With an understanding of the subject you don't need to rely on what the 'experts' tell you – you can make up your own mind. Knowing a bit about probability lets you manage risk and decide whether taking a chance is worth it. More advanced forms of this kind of maths are used to find out about the way diseases spread and the effects of global warming.
### Algebra and equations
A real world example of using algebra is pricing. Say you have rs. 5 and you want to buy a drink that costs rs 1.00 and spend what's left on cookies at 75 paisa each, how many cookies can you get? You can use simple algebra to work it out – 0.75x + 1.00 = 5 When you're looking at the cakes in a shop, you probably think of your variables as 'tasty' rather than x, but it's the same process. It's just that in your maths class you're taught the most general case so it can be applied to everything.
### Fractions, decimals and percentages
We use a decimal system to write down numbers. The word decimal comes from the Greek word for 10, and our system is based on the number 10. Every positive whole number can be written down using the 10 symbols 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. With the additional help of the minus sign and the decimal point we can write down any number as accurately as we want.
But sometimes the bare numbers don't tell you what you need to know. In practical situations we're also likely to use proportion – expressed as ratios and fractions. If chefs don't get the proportion between the ingredients right when they're cooking they will soon run out of customers. Many materials used to repair or build things, like plaster or certain glues, are made up of various components that need to be mixed in the right proportions. Music is also based on proportion. In short, there's no getting away from decimals, fractions and percentages.
Understanding numbers is as fundamental as knowing how to read. The maths you are learning now is designed to help you. The more you work at it, the more you will be rewarded with a better understanding of what's going on in the world around you. And when you know what's happening, you can make a difference. |