一个半径12米的半圆形鱼池,计划在它的周围围一圈篱笆,篱笆至少长多少米?
把算式写完整. 327+915 =327+ + + = + + = + = 705﹣398 =705﹣ + = + = .
163×39﹣163×29.
699+736+101+364.
怎样简便就怎样算:××2442×(﹣)(+)××﹣×.
252+318+248+82.