ON March 14 this year (2013), all eyes and ears will be directed to Mnazi Mmoja in the city of Dar es Salaam where the pi day celebration will be held for the first time outside an educational institution since it was started in Tanzania.

The first attempt was in 2004 when it was inaugurated at the Tanzania Institute of Education (TIE). Our correspondent BENIEL SEKA informs us more about the day. WHEN you mention Pi-Day many people ask "What is pi? Who discovered it? What is its importance?

Why set a special day for pi?" and so on. Those who are already aware of Pi Day will have to bear with us as we explain the concept to our comrades who are hearing it for the first time.

If you are a veteran, you will still learn something new, so do not stay away because there is a lot of new things coming. By definition, pi (pronounced as "pai") is the ratio of the circumference of a circle to its diameter. In other words, it is circumference of a circle divided by its diameter.

Pi is always the same number, no matter which circle you use to compute it. Mathematicians call such a number a constant. Pi is a constant you can easily find practically. Try it and you will find that it is one of the most interesting activities to do. Just take a circular object, measure the length of the distance around the object (circumference) and the distance from one point on the circle to the opposite end through the centre (diameter).

Then divide the circumference by the diameter. Do this for various circular objects. If you do it accurately you will note that the ratio is close to 3.14 when you round it to two decimal places. Pi is approximately 3.14 when taken to two decimal places. Pi- Day has been created from this value of pi. Pi-Day is on the 14th of March. Three (3) is used to represent the third calendar month (March) and 14 represents the 14th day.

For many practical cases you can use 3.14 but if you want a better approximation you can use a computer to get it. The approximation to 5 decimal places is 3.14159 and to 20 decimal places it is 3.14159265358979323846. The mathematicians who created Pi-Day also suggested the next five digits be used to determine the pi hour. Therefore, 1:59:26 pm is regarded as the pi hour.

That is one o'clock, 59 minutes and 26 seconds. It certainly seems knowing the value of pi to four decimal places suits most people's everyday needs. However, some mathematicians are not satisfied with that. For example, William Shanks, a British mathematician, spent 20 years doing calculations by hand and obtained the value of pi to 707 decimal places. He published his results in 1873. Sadly, he had made an error in the 528th decimal place which went on undetected until 1945.

In 1948, John W French Jr and D.F. Ferguson published pi to 808 decimal places. You should now have noticed that pi is an infinite decimal. Unlike numbers such as 5, 2.6 and 1.56, which have finitely many nonzero numbers to the right of the decimal place, pi has infinitely many numbers to the right of the decimal point.

The numbers to the right never repeat in a pattern. However, although many mathematicians have tried to find a pattern, no repeating pattern has been discovered to date. In fact in 1768, Johann Lambert proved that there could not be any such repeating pattern. Historically, pi is a very old number. We know that the Egyptians and the Babylonians knew about the existence of the constant ratio pi, although they did not know its value nearly as well as we know it today.

They had figured out that it was a little bigger than 3. Even the legendary Archimedes knew and used pi in his geometrical work. He is said to have estimated pi by the rational number 22 divided by 7 or 3 EMBED Equation.3 or EMBED Equation. 3. The modern symbol for pi is Ï€ which looks like a cross section of a small stool. The symbol was used for the first time by William Jones in 1706.

Pi (rather than some other Greek letter like alpha, tau or omega) was chosen as the letter to represent the number 3.141592... because the letter (Ï€) in Greek stands for 'perimeter'. Many people recognize the symbol because it has been taught in schools from primary level to higher institutions of learning such as universities. Many people still recall the formula for calculating the area of a circle, "pi r squared."

But how many people go beyond the formula? How to derive the formula is a simple activity that you can perform. It is left for you as an exercise. You will find it quite enjoyable. Ask a veteran to give you a hint or read any mathematics book containing the activity and you will make it. You are now ready to celebrate the 2013 Pi Day on14th March. The celebration will begin with a charity walk from Azania Secondary to Mnazi Mmoja grounds.

There will be led by a trumpets group and escorted along the road by traffic police. There will be a lot of singing, dancing and appeal for support of stakeholders to help efforts to promote children's interest in mathematics. A pre-Pi Day activity will be held at Azania Secondary School a day before. Teachers and pupils near Azania secondary School are invited to attend a seminar intended to motivate pupils to like mathematics.

There will be presentations on application of mathematics in daily life, games, puzzles and number fun. They will also be taught a new method of multiplying numbers using lines. The aim of pre-pi day is to provide more opportunity for interested parties to engage themselves on mathematics activities.

Mathematics exhibitions and mathematical games prepared by invited teachers and pupils from Dar es Salaam schools will be shown. Songs from the pioneers of Pi Day, and 'ngonjera'/poem presented by primary school pupils will 'colour' the day. The guest of honour will join the participants in singing the pi-day birthday song: 'Happy Pi-Day to You' Pi-Day hour, 1:59:26. It will be all joy as you also join in.

Book Publishers and other educational partners will be given an opportunity to display their products. In 2012, the Guest of honour was the Deputy Minister of Education in the Prime Minister's Office for Rural and Local Administration (TAMISEMI) Hon. Kassim Majaliwa (MP). When presenting his speech, the Minister promised the Mathematical Association (MAT/CHAHITA) cooperation in its effort to promote the learning of mathematics in schools and colleges.

He appealed to MAT/CHAHITA to prepare workable plans that his office can assist. "You need to inform us early enough for my implementers to prepare themselves for action," he advised. One of the most felt problems is poor participation of primary school teachers in the MAT/CHAHITA Annual General Meeting (AGM) and seminar.

He also suggested that Pi Day should be extended country-wise for all Tanzanians to access, It is in this spirit, the Pi-day celebration venue is being moved out of institutions and it begins in Mnazi Mmoja. You are all welcome.