[tex]Greatest\ common\ factor\ is\ the\ highest\ number\ by\ witch\ 84\ and\ 196\\and\ 140\ can\ be\ divided\\\\
84:2\\
42:2\\
21:3\\
7:7
\\\\
196:2\\98:2\\49:7\\7:7\\\\140:2\\70:2\\35:5\\7:7\\\\GCF=2^2*7=24\\\\Greatest\ common\ factor\ of\ 84\ and\ 196\ and\ 140 is\ equal\ to\ 24.
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