Write the fraction representing the shaded portion. 

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If $\frac{4}{9}=\frac{8}{x}$ then $x=$.....

Put appropriate number in the $\boxed{}$ to make the following true:

$\frac{2}{7}=\frac{\square }{21}$

Put appropriate number in the $\boxed{}$ to make the following true:

$\frac{12}{24}=\frac{\square }{4}$

Put appropriate number in the $\boxed{}$ to make the following true:

$\frac{3}{7}=\frac{9}{\square }$

Find the fraction equivalent to $\frac{5}{7}$ with numerator $25$.

Find the fraction equivalent to $\frac{5}{7}$  with denominator $42$.

Arrange $\frac{1}{2},\frac{1}{3},\frac{3}{4},\frac{5}{6}$ in ascending order.

Arrange $\frac{1}{4},\frac{1}{6},\frac{3}{8},\frac{5}{12}$ in descending order.