I need to simplify to a proper fraction in the same way as the 2. example for the 3. problem. but I don't understand it

EXPLANATION
Simplifying the fractions to a proper one:
[tex]10\frac{3}{4}=\frac{43}{4}[/tex][tex]4\frac{7}{8}=\frac{39}{8}[/tex]This give us:
[tex]\frac{43}{4}-\frac{39}{8}=\frac{47}{8}[/tex]The answer is 47/8