Toán Lớp 6: Tính nhanh a) 58. 75 + 58. 50 – 58. 25 b) 27. 39 + 27. 63 – 2. 27 c) 128. 46 + 128. 32 + 128. 22 d) 66. 25 + 5. 66 + 66. 14 + 33. 66 e)

Question

Toán Lớp 6:  Tính nhanh a) 58. 75 + 58. 50 – 58. 25 b) 27. 39 + 27. 63 – 2. 27 c) 128. 46 + 128. 32 + 128. 22 d) 66. 25 + 5. 66 + 66. 14 + 33. 66 e) 12. 35 + 35. 182 – 35. 94 f) 48. 19 + 48. 115 + 134. 52 g) 27. 121 – 87. 27 + 73. 34 h) 125. 98 – 125. 46 – 52. 25 i) 136. 23 + 136. 17 – 40. 36 e) 12.35+35.182-35.94 j) 17.93+116.83+17.23

cattien · Answer

a)58.75+58.50-58.25 =58.(75+50-25)                                         =58.100 =5800     b)27.39+27.63-2.27 =27.(39+63-2)                                       =27.100 =2700    c) 128. 46 + 128. 32 + 128. 22 = 128.(46 +32 +22)                                                       = 12.100 = 1200   d)66.25+5.66+66.14+33.66 =66.(25+5.14+33)                                                    =66.(25+70+33)                                                   =66.128 =8448    e) 12. 35 + 35. 182 &ndash; 35. 94 = 35.(12+182 -94)                                                  = 35.100 = 3500   f) 48. 19 + 48. 115 + 134. 52   = 48.(19 +115) +134.52                                                    = 48.134 + 134.52                                                    = 134.(48 +52)                                                    = 134.100 = 13400   g) 27. 121 &ndash; 87. 27 + 73. 34   = 27.(121 -87) +73.34                                                  = 27.34 +73.34                                                  = 34.(27 +73)                                                  = 34.100 = 3400   h) 125. 98 &ndash; 125. 46 &ndash; 52.25= 125.(98 -46) -52. 25                                                   = 125.52 -52.25                                                   = 52.(125 -25)                                                   = 52. 100 = 5200   i) 136. 23 + 136. 17 &ndash; 40. 36= 136.(23 +17) -40.36                                                   = 136.40 -40.36                                                   = 40.(136 -36)                                                   = 40.100 = 4000   e)12.35+35.182-35.94=35.(12+182-94)                                          =35.100=3500   j)17. 93 + 116. 83 + 17. 23  =  17.(93 +23) +116.83                                                  = 17.116 +116.83                                                  = 116.(17+83)                                                  = 116.100 = 11600