# D&T – Thinking About Magnitudes

Ben Craven gave us a talk about quick and easy maths that can be done before a project even starts. This can tell you how realistic an idea is. He gave us a few simple problems that could be worked out fairly simply, without the use of a calculator.

The first of which was fairly simple, we had to work out ‘If you cycled from Glasgow to London, how many times would your wheels rotate?’ Myself and Nadia worked out that they would rotate 300,000 times using an estimated distance between the two cities and the size of a bike wheel. This was pretty easy to do and a fairly good estimate.

The next question was ‘How many breaths do you take in a year?’  we did this by seeing how many breaths Nadia took in 10 seconds then multiplied that by 6, then 60, 25 and 350 (yes we rounded the numbers… not that good at maths). We got 1 million breaths… which was a bit of a underestimate or Nadia’s a really slow breather.

The final question Nadia and I received was ‘If you piled everyone in the world into a cone with 45 degree sides, how high would the cone be? How long would it take you to walk to the top?’  We both imagined every one piled into an ice cream cone – the poor person right at the bottom crushed to death. After a long time we just managed to get an answer of 1km just before the end and we were right! However my guess of 20 minutes for walking to the top was a bit lame…. I was thinking of climbing up a mountain.

Overall the exercise was fun and good to use to see whether a future project is viable or not. Definitely useful for me because my logic is not very good under pressure…

[stag_button url=”http://bencraven.org.uk/” style=”light-blue” size=”small” type=”round” target=”_self”]Ben Craven’s Website[/stag_button]