There are hundreds of online bookmakers and they often
disagree when pricing up sporting events. It is then often possible to bet
all results and still make a profit.
This is known as arbitrage, or an arb.
Enter prices into the boxes in fractions (5/1, 9/4 etc)
One set of odds per box. You can convert from decimal here
If the total odds % are LESS than 100 then
each outcome can be bet for a guaranteed profit.
Another use we have discovered is the
calculation of stakes needed to cover two from three results. For instance, in a
football match enter the away and draw odds to find the stakes needed to bet
your team "not to lose".