Question

1/4k+1/5k+1/7k=5 cat este k?​

Answer 1

Răspuns:

k = $\frac{83}{700}$, k = 0.11857...

Explicație pas cu pas:

$\frac{1}{4k} +\frac{1}{5k} +\frac{1}{7k} =5\\\\\frac{35}{140k} +\frac{28}{140k} +\frac{20}{140k} =5\\\\\frac{35+28+20}{140k} =5$

$\frac{35+48}{140k} =5\\\\\frac{83}{140k}=5\\\\k=\frac{83}{140*5}$

$k=\frac{83}{700} \\\\k=0.11857$

Succes! :)