\(\left(\dfrac{3}{5}+\dfrac{1}{15}-\dfrac{6}{10}\right):a=\dfrac{1}{30}\\ \left(\dfrac{3\times6}{5\times6}+\dfrac{1\times2}{15\times2}-\dfrac{6\times3}{10\times3}\right):a=\dfrac{1}{30}\\ \left(\dfrac{18}{30}+\dfrac{2}{30}-\dfrac{18}{30}\right):a=\dfrac{1}{30}\\ \left(\dfrac{18+2-18}{30}\right):a=\dfrac{1}{30}\\ \dfrac{2}{30}:a=\dfrac{1}{30}\\ a=\dfrac{2}{30}:\dfrac{1}{30}\\ a=2.\)
=>(18/30+2/30-18/30):a=1/30
=>2/30:a=1/30
=>a=2
\(\left(\dfrac{3}{5}+\dfrac{1}{15}-\dfrac{6}{10}\right):a=\dfrac{1}{15}\\ \left(\dfrac{3}{5}+\dfrac{1}{15}-\dfrac{3}{5}\right):a=\dfrac{1}{15}\\ \dfrac{1}{15}:a=\dfrac{1}{15}\\ a=\dfrac{1}{15}:\dfrac{1}{15}\\ a=1.\)
