2019-04-022019-04-021991Fishbyte 9(2): 50-54https://hdl.handle.net/20.500.12348/3103Assuming a known length-weight relationship, the formula for calculating the mean weight from grouped length statistics is recapitulated. Then a simple analytical method for calculating mean weight from basic length statistics is developed which applies when lengths are approximately log-normally distributed or when normally distributed with a coefficient of variation (sd/mean) less than ca. 1/3. The method can be applied to other length distributions as well provided that the coefficient of variation is small.application/pdfCC BY 4.0Journal Article