改正:
(n 不为0)
根据上面的规律计算:
⑴
⑵
①×+×
②48×(+)
③×48
④13×-
⑤+
⑥+
①×-×
②×11+
③×16×
④(+)×24
⑤4.8×(-)
⑥2021×
①21÷0.5÷0.6
②125×88
③2.5×32×12.5
④
⑤
⑥61×40%+38× +0.4