1) ( 41,543 + 78,7 ) + 58,457 = ( 41,543 + 58,457 ) + 78,7 = 100 + 78,7 =

    = 178,7.

2)  6,67 + 5,21 + 4,33 + 4,79 = ( 6,67 + 4,33 ) + ( 5,21 + 4,79 ) = 11 + 10 =

    = 21.