Identify the equation with two fractions set equal to each other: ( frac{a}{b} = frac{c}{d} )
Multiply the numerator of the left fraction by the denominator of the right fraction: (a cdot d)
Multiply the numerator of the right fraction by the denominator of the left fraction: (c cdot b)
Set the products equal: (a cdot d = c cdot b)
Solve the resulting equation for the variable
Check any restrictions (denominators not equal to zero) if applicable