A.增加10 | B.减少10 | C.不变 |
A.537-200-2 | B.537+200-2 | C.537-200+2 |
A.327-268+32=327-(268+32) | B.430-297=430-300-3 | C.223+401+73=(223+73)+401 |
A.190 | B.154 | C.200 |
A.加法交换律 | B.加法结合律 | C.加法交换律和加法结合律 |
A.160 | B.320 | C.640 | D.无法确定 |
A.90 | B.110 | C.370 | D.380 |
A.△-☆=○ | B.☆-〇=△ | C.〇-△=☆ |
A.277 | B.335 | C.420 |
A.30 | B.45 | C.90 | D.180 |