[tex] M_{a}= \frac{a+b+c+d}{4}=14 [/tex]
a+b+c+d=4·34=136
[tex] \frac{a}{2} = \frac{b}{3} = \frac{c}{5} = \frac{d}{7} = \frac{a+b+c+d}{2+3+5+7} = \frac{136}{17} =8[/tex]
primele 4 numere prime 2; 3; 5; 7
[tex] \frac{a}{2} =8[/tex] ⇒ a=16
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