Question

sfertul unui nr natural se aduna cu jumatatea nr si se obtine 69

Answer 1

$\frac{a}{4} + \frac{a}{2} =69 amplificam\\ a+2a=276 \\ 3a=276 \\ a=276:3 \\ a=92$

Answer 2

$\frac{n}{4}+ \frac{n}{2}=69\;|\cdot4\Rightarrow n+2n=4\cdot69\Rightarrow 3n=276\Rightarrow n=\frac{276}{3}\Rightarrow n=92.$

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