Thực hiện phép tính :
\(\eqalign{ & a)\;16 – \left( {17 – 12} \right) + 11 \cr & b)\;24 – {4^2}:4.2 + 3 \cr & c)\;{5.3^4} – {4^3}:8 \cr & d)\;168:3 – 7.5 + {5^2}.4 \cr & e)\;39.213 + 87.39 \cr & g)\;80 – \left[ {130 – {{\left( {12 – 4} \right)}^2}} \right] \cr & h)\;12.\left( {{2^3} – 5} \right) – 45:5 \cr & i)\;{10^2} – \left[ {90:\left( {{5^5}:{5^3} – 2.5} \right)} \right]. \cr} \)
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\(\eqalign{ & a)\;16 – \left( {17 – 12} \right) + 11 \cr&\;\;\;= 16 – 5 + 11 = 11 + 11 = 22 \cr & b)\;24 – {4^2}:4.2 + 3\cr&\;\;\; = 24 – 16:4.2 + 3 = 24 – 4.2 + 3 \cr&\;\;\;= 24 – 8 + 3 = 16 + 3 = 19 \cr & c)\;{5.3^4} – {4^3}:8 = 5.81 – 64:8 \cr&\;\;\;= 405 – 8 = 397 \cr & d)\;168:3 – 7.5 + {5^2}.4 \cr&\;\;\;= 56 – 35 + 25.4 = 56 – 35 + 100 \cr&\;\;\;= 21 + 100 = 121 \cr & e)\;39.213 + 87.39 = 39.(213 + 87) \cr&\;\;\;= 39.300 = 11700 \cr & g)\;80 – \left[ {130 – {{\left( {12 – 4} \right)}^2}} \right] \cr&\;\;\;= 80 – (130 – {8^2}) \cr&\;\;\;= 80 – (130 – 64) = 80 – 66 = 14 \cr & h)\;12.\left( {{2^3} – 5} \right) – 45:5 \cr&\;\;\;= 12.(8 – 5) – 45:5 \cr&\;\;\;= 12.3 – 45:5 = 36 – 9 = 27 \cr & i)\;{10^2} – \left[ {90:\left( {{5^5}:{5^3} – 2.5} \right)} \right] \cr&\;\;\;= 100 – {\rm{[}}90:({5^2} – 2.5){\rm{]}} \cr & \;\;\; = 100 – {\rm{[}}90:(25 – 10){\rm{]}} \cr&\;\;\;= 100 – (90:15) = 100 – 6 = 94 \cr} \)