Express it as:
[tex]-\frac{12.7}{1}[/tex]Multiply by 10 the numerator and the denominator:
[tex]-\frac{12.7}{1}\times\frac{10}{10}=-\frac{127}{10}[/tex]so:
[tex]-12.7=-\frac{127}{10}[/tex]----------------------
For a mixed number, we can use the following formula:
[tex]a\frac{b}{c}=\frac{ac+b}{c}[/tex]So:
[tex]11\frac{1}{4}=\frac{11\cdot4+1}{4}=\frac{44+1}{4}=\frac{45}{4}[/tex]