213+45+87=(+)+45 (1.67+5.88)+0.12=+(+)
57×25×4=57×(×) (8+4)×125=×+×
+++
=(8.9+)+(3.6+)
=+
=(元)
①87.5-63.9+2587.5+25-63.9
②10-2.7-7.310-(7.3-2.7)
①5.6+12.85-9.76
②16-8.49+5.19
③14.68-0.56-6.44
④14.68-9.68+7.4
⑤14.68-(9.68-7.4)
⑥2.43+3.34+6.66+2.57
①38.17+0.15+71.83
②6.67+5.2+1.45
③21.33-4.67+8.12
④14.12-7.42-5.58
⑤14.6-3.98+5.4-0.02
⑥17.65-(0.65+9.9)