Maths help please to create a 100% book

To get the equivalent % for the Decimal Odds, you divide the Odds into 100....

Therefore 100/1.91 = 52.36%
          100/3.5  = 28.57%
          100/3.6  = 27.78%

Total Book = 108.71%

If you wanted to make it a 100% Book then, Factor each % by 100/108.71

To give you the percentages of 48.16%; 26.28%; 25.55%

Now Divide these percentages into 100, Giving you Odds of: 2.08;3.81;3.91

Many thanks for that however that doesn't seem to work when you get a big odds on shot and a big outsider.

For example a game where the prices are 10.0 5.0 and 1.3

Using your formula I end up with prices of 10.69 5.35 and 1.39 which does indeed make a 100% book. However surely the 10 goes much bigger and the 1.3 cannot possibly get to 1.39

Apologies if I doing something really stupid but I just can't get my head round this!

.. just divide each one with 92%  :)

e.g. 1.91/0.92=2.076

www.advancedbetcalc.com/Fair%20Coefficient.aspx

Thanks to you both for your reply which works until you get a football match of 10 5 and 1.3

Also tennis Murray today at Lads 8.5 and 1.07 95% book.

Doing what you say gives 'true' odds of 8.95 and 1.12 - surely this can't be correct?

Your comments would be most welcome and greatly appreciated.

using the Murray match prices 8.4 (11.9% chance) and 1.07 (93.46%) = 105.36%

reduce each % chance by around 2.78%

prices are now 1.11 and 10.5 (90.09% and 9.52%)

* sorry, reduce by 2.68%

calmbefore, do you really need to be so precise?

:)

i know what's bothering you.. but this is how it is. Bookies predict "true" (chances) odds..

for example: 1.11 (90%) vs 10.00 (10%), then they introduce margin (to make profit) of 5% and reduce both odds by that 5%. Getting 1.11/1.05=1.06 & 10/1.05=9.52.
So when people bet - Bookie wants $1000 on 1.06 and $111 on 9.52 thus having "money in"= $1111 and in any outcome "money out"= 1060, earning around 5%.

Now, they could make 1.09 vs 7.50 but then they lowered 1.11 "only by 2% and that is "dancing on the edge" and will probably open possibility for arbitrage betting in combination with Bookies who "went in opposite direction" and bookies don't like arbers :)

I still wonder why you
need the answer to the
opening question. GL if
you get the figures you
need.