Each side has 1/6 chance (or 16%) so you can work out fair value by dividing 1 / 0.16 (16%) and getting the number 6.00 (decimal odds) or 5/1 (fractional odds). So if I offer you a bet at a price of better than 6.00 you should take it - if it's less than that (say 5.00) you should not take it - even though the price of 5.00 sounds high - it is not value.