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## 'Estimating Time' printed from http://nrich.maths.org/

Well done to everyone who had a go at this problem. Lots of you suggested that a good way of estimating time was to say a certain phrase that lasts around one second over and over again.

Yiyi from Harrow International School in Hong Kong shared these thoughts:

People are usually better at estimating shorter amounts of time such as 10 or 15 seconds than 30 or 60 seconds because if a person is counting too fast or too slow a longer time such as 60sec, it allows them more time to go even faster or slower giving them a wider range of time to do so.

So people that are better at estimating 10 seconds are not always good at estimating a longer time. But there are some that realise they are counting at the wrong pace during the middle therefore count more to the opposite pace (faster to slower / slower to faster).

Normally when the first attempt of a person is over-estimated the second would be under as the person tries to count slower but the pace of counting might change during the middle so it won't always be the opposite of the first attempt. The same with underestimating on the first attempt.

Some people estimate time by saying a word of a specific length. But it depends on the speed that it's said because just saying it does not always give the same time because you could say it faster and slower.

Thanks also to Ahrus, Aliyah, Zahra, Isha, Bilal, Aaqib and Mohammed, all students from Dixons Trinity Academy in Bradford, for their contributions.

Having carried out various experiments they then commented on how they could be improved; they pointed out that next time, to be able to draw reliable conclusions from their experiments, they would want to perform a larger number of trials and use a larger sample of people. They appreciated the value of communicating their results clearly and used averages, tables and graphs. Thank you
all.