bn (32492+350.12+33242+319.52)-368004919 4×3 367250025-36680.4919 44.5106 ∑x-C=,(3272+36382+35782+27812)-3680491 37064.2275-36680.4919=383.735637064.2275 36680.4919 383.7356 (327.2 363.8 357.8 278.1 ) 36680.4919 4 3 1 1 44.5106 36725.0025 36680.4919 (324.9 350.1 332.4 319.5 ) 36680.4919 4 3 1 1 2 2 2 2 2 . . 2 2 2 2 2 .. = − = + + + −  = − = = = − + + + −  = = −   x C an SS x C bn SS B j A i