An example coding device, such as a video coding (encoding or decoding) device is configured to determine a plurality of estimator functions to be used to calculate a probability of a symbol having a particular value, wherein the symbol is to be binary arithmetic coded according to the probability, and wherein the estimator functions do not include division operations; determine a plurality of weights for the plurality of estimator functions such that when the respective weights are applied to the estimator functions, a resulting sum of outputs of the plurality of estimator functions yields the probability; calculate the probability of the symbol having the particular value, including: execute the estimator functions without using the division operations to determine the outputs; and calculate a sum of the outputs as the probability; and binary arithmetic code the symbol according to the probability of the symbol having the particular value.