四年级 口算 估算1因数的末尾有0。208013303220 507025040 4030032030 2102041010 3302015030 4012094010 2024023030 501402除数是整十数的口算。24080 3505048060 450509030 1806016020 402072080 4207080020 6307039030 6606046020 320203估算。2941 4910280227 496513853 6890990129 4930410898 5184190032 3557054160 3194049170 7258040748 6056119852 208424混合运算中的口算。1202080302703020032040400806050(408)(8238)28109060403202012020答案1160039066035001000012000960042004100660045004800940048006900700023789338296409131123163120050002400025000200063000270001500010000200003059879810454248039192300250240296406
