Maths in everyday life - 2

Transport
You wait for the bus. Maths is used to timetable buses, trains and planes, taking into account the limited stocks of vehicles, the cost of fuel and the number of people wanting to use them for various journeys across the day. It is used to decide the timing of traffic lights, and to understand traffic flow and congestion. This is another application of operational research (see planning).
Maths also affects the designs of these vehicles, particularly planes, cars and boats. Aerodynamics, another application of fluid dynamics, is obviously vital in designing a plane that can actually fly, but is also important in designing any sort of vehicle to move as smoothly through the air as possible so that it can go faster and take less fuel.

Understanding chance and risk
You get off the bus and someone is selling tickets in a raffle for a new car. Should you buy one? What are the chances of you winning in this, or in any other, lottery? All games of chance are governed by probabilities of events happening. If you understand probability, you have a much better chance of coming out on top, or in deciding that it's not worth spending your money at all.
The bus got stuck in traffic, and you arrived at your destination really late. Should you ride your bike next time, you wonder. But is that too risky? And, if you do, should you wear a helmet?
Your friend calls you to say she has had some negative test results from the doctor. Is she definitely sick, or what are the chances that the test is wrong and she is not sick at all? There are a number of treatment options available, but all have different rates of success and different side effects. To decide which one to take, she will need to weigh up the risks of side effects of each treatment against the chances of success, using the probabilities of each of these.
Business and industry also need to make decisions about risk and chance and need mathematicians - or operational researchers - to help them with this.

Communicating
Finally you get home and get a chance to check your email. Computers store all information as binary numbers, and use mathematical operations to manipulate this information, whether you are editing an email, resizing a photo or setting preferences in your web browser.
Computers communicate digitally, sending packets of information across networks or wires, fibre optic cables and phone lines. The way this information is encoded uses maths. Maths is also used to create better compression methods, so that you can download mp3s faster, or that movie makers can fit longer movies and more special features on DVDs.