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用简便方法计算352-98725+363+75786+643-586306-197495+249547+158-347970-346-154263-98+37934-257-234.

题目详情
用简便方法计算
352-98725+363+75786+643-586
306-197495+249547+158-347
970-346-154263-98+37934-257-234.
▼优质解答
答案和解析
(1)352-98
=352-(100-2)
=352-100+2
=252+2
=254;

(2)725+363+75
=725+75+363
=800+363
=1163;

(3)786+643-586
=786-586+643
=200+643
=843;

(4)306-197
=306-(200-3)
=306-200+3
=106+3
=109;

(5)495+249
=500-5+249
=500+249-5
=749-5
=744;

(6)547+158-347
=547-347+158
=200+158
=358;

(7)970-346-154
=970-(346+154)
=970-500
=470;

(8)263-98+37
=263+37-98
=300-98
=202;

(9)934-257-234
=934-234-257
=700-257
=443.