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计算:(1)76+137+80+139+74+143+83+137+84+87+137+78+75+142.(2)[(83+33)×13+66]×2+83×24.(3)787×53+213×71+187×18.(4)13×125-25×27+75×21+175×3.(5)12×29×13+31×11×17-12×13×18-11×17×19.

题目详情
计算:
(1)76+137+80+139+74+143+83+137+84+87+137+78+75+142.
(2)[(83+33)×13+66]×2+83×24.
(3)787×53+213×71+187×18.
(4)13×125-25×27+75×21+175×3.
(5)12×29×13+31×11×17-12×13×18-11×17×19.
▼优质解答
答案和解析
(1)76+137+80+139+74+143+83+137+84+87+137+78+75+142
=70+140+140+80+140+70+140+80+90+90+140+72+78+142
=140×6+70×2+80×2+90+2+150+2
=840+140+160+180+152
=1472

(2)[(83+33)×13+66]×2+83×24
=[83×13+33×13+33×2]×2+83×24
=83×26+33×26+83×24+33×4
=83×(26+24)+33×(26+4)
=83×50+33×30
=4150+990
=5140

(3)787×53+213×71+187×18
=41711+15123+3366
=60200

(4)13×125-25×27+75×21+175×3
=25×65-25×27+25×63+25×21
=25×(65-27+63+21)
=25×112
=25×4×18
=100×18
=1800

(5)12×29×13+31×11×17-12×13×18-11×17×19
=12×13×(29-18)+11×17×(31-19)
=11×12×13+11×17×12
=11×12×(13+17)
=132×30
=3960