[54/15-(0.25+1/3)*7.2]*24/5

[54/15-(0.25+1/3)*7.2]*24/5
[54/15-(0.25+1/3)*7.2]*24/5

[54/15-(0.25+1/3)*7.2]*24/5
原式=（3.6-1.8-2.4）×4.8
=-0.6×4.8
=-2.88

由上可得
原式=【18/5-(7*(36/5)/12)】*24/5
=（18/5-21/5）*24/5
=-3*24/25
=-72/25