746-587+4874734-(3734-159)+523-(423-141
746-587+4874734-(3734-159)+523-(423-141)...
746-587+4874734-(3734-159)+523-(423-141)
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(1)746-587+487 =746-(587-487), =746-100, =646;
(2)4734-(3734-159)+523-(423-141) =4734-3734+159+523-423+141, =4734-3734+(159+141)+(523-423), =1000+300-100, =1200. |
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