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先找规律,再计算.210+220+230+240+250=×320+340+360+380=×.

题目详情
先找规律,再计算.
210+220+230+240+250=___×___
320+340+360+380=___×___.
▼优质解答
答案和解析
(1)210+220+230+240+250
=(210+250)+(220+240)+230
=230×2+230×2+230
=230×(2+2+1)
=230×5
=1150;

(2)320+340+360+380
=(320+380)+(340+360)
=350×2+350×2
=350×(2+2)
=350×4
=1400;
故答案为:230,5;350,4.