----- Nội dung dịch tự động từ ảnh ----- 1) \(\left( \frac{-25}{27} \ \frac{31}{42} \right) - \left( \frac{-7}{27} \ \frac{3}{42} \right)\) 2) \(\left( \frac{-13}{25} \ \frac{5}{32} \right) \cdot \left( \frac{-13}{25} \right) \cdot (-64)\) 3) \(\frac{3}{8} - \frac{23}{14} \ - \frac{3}{8} - \frac{9}{14}\) 4) \(\frac{5}{12} + \frac{4}{5} - \frac{3}{4} + \frac{1}{4}\)
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35 Tham khảo câu trả lời từ Trợ lý ảo Lazi Let's simplify and calculate each of the expressions step by step. ### 1) \[ \left( \frac{-25}{27} \frac{31}{42} \right) - \left( \frac{-7}{27} \frac{3}{42} \right) \] First, we need to multiply the fractions: 1. \(\frac{-25}{27} \times \frac{31}{42} = \frac{-775}{1134}\) 2. \(\frac{-7}{27} \times \frac{3}{42} = \frac{-21}{1134}\) Now, we combine the two results: \[ \frac{-775}{1134} - \frac{-21}{1134} = \frac{-775 + 21}{1134} = \frac{-754}{1134} \] Now simplify: \[ \frac{-754}{1134} = \frac{-377}{567} \quad (\text{dividing both by 2}) \] ### 2) \[ \left( \frac{-13}{25} \times \frac{5}{32} \right) - \left( \frac{-13}{25} \times (-64) \right) \] Calculating each term: 1. \(\frac{-13}{25} \times \frac{5}{32} = \frac{-65}{800}\) 2. \(\frac{-13}{25} \times (-64) = \frac{832}{25}\) Finding a common denominator (which can be \(800\)): 1. \(\frac{832 \times 32}{25 \times 32} = \frac{26624}{800}\) Combining: \[ \frac{-65}{800} + \frac{26624}{800} = \frac{26624 - 65}{800} = \frac{26559}{800} \] ### 3) \[ \frac{3}{8} - \frac{23}{14} - \frac{3}{8} - \frac{9}{14} \] Finding the common denominator which is \(56\): 1. \(\frac{3}{8} = \frac{21}{56}\) 2. \(\frac{-23}{14} = \frac{-92}{56}\) 3. \(\frac{3}{8} = \frac{21}{56}\) 4. \(\frac{-9}{14} = \frac{-36}{56}\) Combining: \[ \frac{21 - 92 + 21 - 36}{56} = \frac{-86}{56} = \frac{-43}{28} \] ### 4) \[ \frac{5}{12} + \frac{4}{5} - \frac{3}{4} + \frac{1}{4} \] Convert to a common denominator. The LCM of \(12, 5, 4\) is \(60\): 1. \(\frac{5}{12} = \frac{25}{60}\) 2. \(\frac{4}{5} = \frac{48}{60}\) 3. \(\frac{3}{4} = \frac{45}{60}\) 4. \(\frac{1}{4} = \frac{15}{60}\) Now combine: \[ \frac{25 + 48 - 45 + 15}{60} = \frac{43}{60} \] --- ### Final Results: 1) \(\frac{-377}{567}\) 2) \(\frac{26559}{800}\) 3) \(\frac{-43}{28}\) 4) \(\frac{43}{60}\)