\(\eqalign{ & a)\;27.75 + 25.27 - 150 \cr&\;\;\;= 27.(75 + 25) - 150 \cr&\;\;\;= 27.100 - 150 \cr&\;\;\;= 2700 - 150 = 2550 \cr & b)\;163.23 + 163.17 + 37.40 \cr&\;\;\;= 163.(23 + 17) + 37.40 \cr &\;\;\; = 163.40 + 37.40 \cr&\;\;\;= 40(163 + 37) = 40.200 = 8000 \cr & c)\;\left( {{{10}^2} + 8} \right):{3^2} + {2014^0} \cr&\;\;\;= (100 + 8):9 + 1 \cr & \;\;\; = 108:9 + 1 = 12 + 1 = 13 \cr & d)\;12:\left\{ {390:\left[ {500 - \left( {125 + 35.7} \right)} \right]} \right\} \cr&\;\;\;= 12:{\rm{\{ }}390:{\rm{[}}500 - (125 + 245){\rm{]\} }} \cr & \;\;\; = 12:{\rm{[}}390:(500 - 370){\rm{]}} \cr&\;\;\;= 12:(390:130) = 12:3 = 4 \cr} \) Đề bài Thực hiện phép tính: \(\eqalign{ & a)\;27.75 + 25.27 - 150 \cr & b)\;163.23 + 163.17 + 37.40 \cr & c)\;\left( {{{10}^2} + 8} \right):{3^2} + {2014^0} \cr & d)\;12:\left\{ {390:\left[ {500 - \left( {125 + 35.7} \right)} \right]} \right\}. \cr} \) Lời giải chi tiết \(\eqalign{ & a)\;27.75 + 25.27 - 150 \cr&\;\;\;= 27.(75 + 25) - 150 \cr&\;\;\;= 27.100 - 150 \cr&\;\;\;= 2700 - 150 = 2550 \cr & b)\;163.23 + 163.17 + 37.40 \cr&\;\;\;= 163.(23 + 17) + 37.40 \cr &\;\;\; = 163.40 + 37.40 \cr&\;\;\;= 40(163 + 37) = 40.200 = 8000 \cr & c)\;\left( {{{10}^2} + 8} \right):{3^2} + {2014^0} \cr&\;\;\;= (100 + 8):9 + 1 \cr & \;\;\; = 108:9 + 1 = 12 + 1 = 13 \cr & d)\;12:\left\{ {390:\left[ {500 - \left( {125 + 35.7} \right)} \right]} \right\} \cr&\;\;\;= 12:{\rm{\{ }}390:{\rm{[}}500 - (125 + 245){\rm{]\} }} \cr & \;\;\; = 12:{\rm{[}}390:(500 - 370){\rm{]}} \cr&\;\;\;= 12:(390:130) = 12:3 = 4 \cr} \)
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