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media aritmetica a trei numere rationale pozitive este egala cu 17 . media aritmetica a ultimelor doua este 16.stiind ca al doileanumar este egal cu o treime din al treilea aflati numerele


Răspuns :

[tex]M_{aritmetica} = \frac{\frac{a}{b} + \frac{c}{d} + \frac{e}{f} }{3}=17[/tex]

[tex]\frac{a}{b} + \frac{c}{d} + \frac{e}{f} =17*3[/tex]

[tex]\frac{a}{b} + \frac{c}{d} + \frac{e}{f} =51[/tex]

[tex]M_{aritmetica} = \frac{\frac{c}{d} + \frac{e}{f} }{2}=16[/tex]

[tex]\frac{c}{d} + \frac{e}{f} =16*2[/tex]

[tex]\frac{c}{d} + \frac{e}{f} =32[/tex]

[tex]\frac{b}{c} = \frac{1}{3} * \frac{e}{f} [/tex]

[tex]\frac{1}{3} * \frac{e}{f} + \frac{e}{f} =32[/tex]

[tex]\frac{e}{f} + 3*\frac{e}{f} =32*3[/tex]

[tex]4*\frac{e}{f} =32*3[/tex]

[tex]\frac{e}{f} =\frac{96}{4}[/tex]

[tex]\frac{c}{d} + \frac{96}{4} =32[/tex]

[tex]\frac{c}{d} =32-\frac{96}{4}[/tex]

[tex]\frac{c}{d} =\frac{32*4-96}{4}[/tex]

[tex]\frac{c}{d} =\frac{128-96}{4}[/tex]

[tex]\frac{c}{d} =\frac{32}{4}[/tex]

[tex]\frac{a}{b} + \frac{c}{d} + \frac{e}{f} =51[/tex]

[tex]\frac{a}{b} + \frac{96}{4} + \frac{32}{4} =51[/tex]

[tex]\frac{a}{b} + \frac{96+32}{4}=51[/tex]

[tex]\frac{a}{b} + \frac{128}{4}=51[/tex]

[tex]\frac{a}{b} =51-\frac{128}{4}[/tex]

[tex]\frac{a}{b} =\frac{51*4-128}{4}[/tex]

[tex]\frac{a}{b} =\frac{204-128}{4}[/tex]

[tex]\frac{a}{b} =\frac{76}{4}[/tex]

Numerele sunt: [tex]\frac{a}{b} =\frac{76}{4};\frac{c}{d} =\frac{32}{4};\frac{e}{f} =\frac{96}{4}[/tex]

Verificare:

[tex]M_{aritmetica} = \frac{\frac{a}{b} + \frac{c}{d} + \frac{e}{f} }{3}=\frac{\frac{76}{4} + \frac{32}{4} + \frac{96}{4} }{3}=\frac{19+8+24}{3}=\frac{51}{3}=17[/tex]