Answer :
[tex]Greatest\ common\ factor\ is\ the\ highest\ number\ by\ witch\ 72\ and\ 96\\ and\ 120\ can\ be\ divided\\\\
72:2\\
36:2\\
18:2\\9:3\\3:3\\\\
96:2\\
48:2\\
24:2\\12:2\\
6:2\\3:3\\\\120:2\\60:2\\
30:2\\15:3\\5:5\\\\GCF=2^3*3=24\\\\Greatest\ common\ factor\ of\ 72\ and\ 96\ and\ 120\ is\ equal\ to\ 24.
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