what is variance of a summative variable how to calculate the variance of the weight of a unit if the units are all of the same weight average weight of one sms unit calculate variance of weight of units how to determine variance of a compound variable average weight for a unit of weight average variance in a weighted package variance of sum of a compound variable average weight of units average weight variance variance of summation average weight of a metric packet average weight of a packet of 10 units how to find variance of summation how to find variance of a summation and compound variable how to determine variance of a compound variable variance of weight how to find variance in math how to find the variance of summation and compound variables variance of the sum of weight