①8.47+12.53-1.2 ②50-19.8-20.2 ③19.4+4.58+5.42
16.3-7.6-2.4 8.8+4.3+5.2
9-(3.02+1.25) 2.13-1.59+0.87
175-15-45◯175-45-15
186-(86+67)◯186-86-67
589-326-74◯589-(326+74)
316-95-116◯316-116-95
我发现:( )。(用字母表示)
32+6.4+68+3.6 27+0.4-8.27 18.51-9.03-0.97
①14.37+2.75-5.63
②90.3-2.54-11.46
③2.5+1.32+2.68
①6000÷25
②73.2+27.3+72.7
③42.5-16.41-3.59
④29.46-(5.8-0.08)
⑤65×[(500-32)÷18]
5.4+0.74+4.6=5.4++0.74
4.04+13.57+2.43=4.04+(◯)
48.72-0.2-0.8=48.72-(◯)
2.3+5.4+8.7+3.6=( ◯ )◯( ◯ )