\(\boxed{\color{red}\text{Dividing a number is same as multiplying its reciprocal}}\)
\(\boxed{\color{olive}\text{Division of a fraction: Exchange the denominator and the numerator and change}\\\color{olive}\div\text{into}\times.} \)
\(\boxed{\color{aqua}\text{If there exists a number x, its reciprocal is}\dfrac{1}{x}}\)
\(\quad\dfrac{1}{6}\div \dfrac{1}{3} \div \dfrac{2}{5}\\=\dfrac{1}{6}\times \dfrac{1}{\dfrac{1}{3}}\times\dfrac{1}{\dfrac{2}{5}}\\ =\dfrac{1}{6}\times 3 \times \dfrac{5}{2}\\=\dfrac{3\times 5}{6\times2}\\=\dfrac{5}{4}\\\color{red}OR\\=1\dfrac{1}{4}\)
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