问题
填空题
根据估算填.
81×30≈______×______=______; 42×29≈______×______=______.
答案
81×30≈80×30=2400;
42×29≈40×30=1200.
故答案为:80,30,2400,40,30,1200.
根据估算填.
81×30≈______×______=______; 42×29≈______×______=______.
81×30≈80×30=2400;
42×29≈40×30=1200.
故答案为:80,30,2400,40,30,1200.