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用递等式计算(能巧算的要巧算)346+128+254599-133-248345+234+2458X3-3X2187-65-87108-7X4

题目详情
用递等式计算(能巧算的要巧算)
346+128+254 599-133-248
345+234+245 8X3-3X2 187-65-87 108-7X4
▼优质解答
答案和解析
346+128+254
=(346+254)+128
=600+128
=728
599-133-248
=599-(133+248)
=599-381
=218
345+234+245
=345+245+234
=690+234
=924
8X3-3X2
=3×(8-2)
=3×6
=18
187-65-87
=187-87-65
=100-65
=35
108-7X4
=27×4-7×4
=4×(27-7)
=4×20
=80