[tex]f = \frac{1.4}{ \frac{10}{21} } = \frac{ \frac{14}{10} }{ \frac{10}{21} } = \frac{14}{10} \div \frac{10}{21} = [/tex]
[tex] = \frac{14}{10} \times \frac{21}{10} = \frac{294}{100} = 2.94[/tex]
