Calculate the weight breakpoint: Based on the below TACT rate, Q100-$4.67, Q300- $4.08, so please compute the weight breakpoint between 100kg and 300kg, which means every weight above the breakpoint is applicable to the next weight bracket, hence a different freight rate, which is usually lower. Calculate in detail. M N Q45 Q100 @300 Q500 Q1000 20 N 150.00 10.84 8.62 4.67 4.08 3.64 3.06.