Răspuns :
a+a/3 +a/4 -5 + 2a/6 = 6720/105 = 64
a+a/3 +a/4+a/3 = 69
a+2a/3 + a/4 = 69
12a+8a+3a= 12*69
23a= 828
a=828:23 = 36.
a+a/3 +a/4+a/3 = 69
a+2a/3 + a/4 = 69
12a+8a+3a= 12*69
23a= 828
a=828:23 = 36.