Coded Averages

Teaching coding inward Statistics i is a fleck of a pain.  My pupils simply don't similar it, in addition to it's difficult for me to larn enthusiastic most something that didn't actually be when I studied Statistics (perhaps because it's non solely necessary?). When I was revising this topic amongst my Year 12s this year, I used a actually uncomplicated real-life example:

Imagine I'm queuing upwards to purchase 4 items of clothing, which cost £29.95, £49.95, £59.95 in addition to £99.95. To hold upwards past times fourth dimension I determine to function out the hateful cost of these 4 items. To brand the numbers easier to bargain with, I add together 5p to each total in addition to and so separate past times 10, giving me £3, £5, £6 in addition to £10. It's really slow to function out the hateful of these 'coded' prices inward my caput - it's £6. And right away I tin uncode that hateful past times multiplying past times 10 in addition to so subtracting 5p (the inverse of the master copy coding).  That rapidly gives me the actual hateful cost of the clothes, which is £59.95.  

Resources
Here's a few resources I've establish for instruction this topic:
There's a express alternative hither so possibly I should write something myself - I'll add together it to my list!