Monday, 30 January 2017

Some Quite Interesting Numbers

Watching last week's QI on the BBC, they had a feature that I thought would be useful in school to ignite some interest in maths. 

What's interesting about these numbers?

The picture is the Mayan zero.

The '2 to the power of...' is the largest known prime number (at the time of writing).

If someone wrote out the numbers 1 - 10 billion in words and organised them in alphabetical order, 8,000,000,085 would be the first odd number.

142,857 is a cyclical number: multiply it by 1, 2, 3, 4, 5 or 6 and the product (each time) is an anagram of it!

Frobenius number - Chicken nuggets are sold in 6s, 9s and 20s. 43 is the largest number of nuggets that can't be bought.   

There you go. Share them as they are, or even make an investigation out of some of them. Quite interesting.

Monday, 2 January 2017

Christmas Countdown Problem

The above shows a Christmas countdown that we have on a window in our kitchen at home from the 1st of December. It's designed to be used like an Advent calendar and only in December (hence having 2 lots of 2 for '22 days to go' and 2 lots of 1 for '11 days to go', but not 2 lots of the other numbers). Today, I noticed that someone has begun a countdown towards Christmas 2017 (don't worry, it's coming down shortly). However, if we were to continue, how many days could not be shown with the numbers available and what 'days to go' are they? For example '222 days to go' can't be shown as there are only 2 lots of 2, but 357 and 356 can both be shown.

Sunday, 1 January 2017

Órlagh's Birthday Riddle

It is true, I know 'cos it's my daughter. I'm going to give that statement to my class this week to see if they can figure out how it can be true.

In case you hadn't already worked it out... She was born on 31/12/2014. She therefore spent sometime (not much) in 2014, also 2015 and 2016. As it's now 2017, that's a fourth (calendar) year. The years are actually irrelevant as the answer is she was born on New Year's Eve and two years and one day later, it's now New Year's Day.