Teaser 2566

[richardp]

Earlier this month, teaser 2566 suggested a series of consecutive
integers, each with 0.9 added (i.e. 130.9, 131.9, 132.9, 133.9 etc)
and asked how many such integers would be needed to give a whole
number average. The published answer was 5.
I simply cannot understand this. The average of such a series either
ends 0.4 or 0.9 depending on whether an odd or even number of terms is
selected. Can anyone shed light on this for me please?
richardp

[Cactus]

Hi Richard,

If you go to the Sunday Times Teasers Site here:

https://sites.google.com/site/sundaytimesteasers/

you will see that the Sunday Times printed this teaser incorrectly, see:

https://sites.google.com/site/sundaytimesteasers/teaser-index-1/q4-2011/teaser-2566

Brian Gladman

[richardp]

Cactus
Thank you so much.
This was really bugging me, and now I understand
Richard

[Cactus]

You are welcome Richard .

If you continue to have an interest in the Teaser Group, it would pay to
use the web site as the discussion group is now rarely used (but you do have
to be registered on the discussion group in order to post comments on the
web site).

Brian