Thursday 4 December 2008

National Science Center, KL


I learnt something from our visit to the Pusat Sains Negara at Bukit Damansara yesterday.

A roundabout number is a number that when you multiply by something, the numbers in it are in the product. An example of a roundabout number is 142857. So,

if multiplied by 2: 142857 x 2 = 285714
if multiplied by 3: 142857 x 3 = 428571

Try multiplying by other numbers. Fascinating, isn't it?
A puzzle:

Draw 4 straight lines to connect all the dots.


[Scroll down for answer.]
















Answer:

Piece of cake?!




2 comments:

Anonymous said...

i tried multiplying - only works up to 6. but you're right - it is fascinating.

Jolene Zheng said...

Hi YP

It seems to work for all numbers except for multiples of 7. Even for bigger numbers, you can detect a pattern (ie for products that have more than 6 digits). Try with an Excel spreadsheet - I find it intriguing!