整十数加,减整十数,)(56-58,3- :,整十数加,减整十数,!,整十数加,减整十数,:,整十数加,减整十数,65.1 ( 6) (5),29.2 ( 9) (2) . 3. 7 4 (47). 4. 7 4 (74,整十数加,减整十数,: 35=30+( ) 57=7+( ) 65=60+( ) 29=9+(,5,20,5,50,整十数加,减整十数,6+70,70+6,60+7,50+2,5+10,整十数加,减整十数,:,整十数加,减整十数,: 56,100 (1,整十数加,减整十数,10,20,30,30),10,30,10,20,3,2,:10,:20,整十数加,减整十数,:,整十数加,减整十数,70,40,40,20,60,20 40,60,20 = 40,60 60,40 = 20,7,4,10,7,57,整十数加,减整十数,10-:58,5,50,9,90,2,20,40,3,43,40,30,70,整十数加,减整十数,5,9,50,90,5,2,50,20,10-:58,整十数加,减整十数,50,10,20,50,10,20,20( 个,40,(20),10-:58,