A-A+
脱式计算(能简算要简算)①67+215+17+1315②1921+57-314③23+59-
问题详情
①
①67+215+17+1315,
=(67+17)+(215+1315),
=1+1,
=2;
②1921+57-314,
=1921+(57-314),
=1921+12,
=5942;
③23+59-23+59,
=(23-23)+(59+59),
=109;
④89+(14-19)+34,
=89+14-19+34,
=(89-19)+(14+34),
=79+1,
=179;
⑤0.58+513+1.12+813,
=(0.58+1.12)+(513+813),
=1.7+1,
=2.7;
⑥11-411-711,
=11-(411+711),
=11-1,
=10.