We will subtract the hours spent for his English test from the hours spent for his math test.
Therefore,
[tex]5\frac{3}{14}-3\frac{6}{7}[/tex]Find the L.C.M of the denominators
Thus,
[tex]5\frac{3}{14}-3\frac{6}{7}=5-3\frac{3\left(1\right?-2\left(6\right)}{14}=2\frac{3-12}{14}=2\frac{-9}{14}=1\frac{14-9}{14}=1\frac{5}{14}[/tex]Hence, he spent 1 5/14hours longer for his math test.