Answer:
[tex]\large\boxed{P=5\dfrac{3}{10}\ cm=5.3\ cm}[/tex]
Step-by-step explanation:
If you want find the perimeter, then you must add all lengths of sides of the given polygon.
[tex]P=AB+BC+CD+DE+EA\\\\AB=1\dfrac{3}{4}\ cm,\ BC=1\dfrac{1}{10}\ cm,\ AE+DC=1\dfrac{1}{5}\ cm,\ DE=1\dfrac{1}{4}\ cm\\\\P=1\dfrac{3}{4}+1\dfrac{1}{10}+1\dfrac{1}{5}+1\dfrac{1}{4}=\left(1\dfrac{3}{4}+1\dfrac{1}{4}\right)+1\dfrac{1}{10}+1\dfrac{1\cdot2}{5\cdot2}\\\\=2\dfrac{4}{4}+1\dfrac{1}{10}+1\dfrac{2}{10}=3+2\dfrac{3}{10}=5\dfrac{3}{10}[/tex]
Other method.
Convert the mixed numbers to the decimal:
[tex]AB=1\dfrac{3}{4}\ cm=1.75\ cm\\\\BC=1\dfrac{1}{10}\ cm=1.1\ cm\\\\AE+DC=1\dfrac{1}{5}\ cm=1.2\ cm\\\\DE=1\dfrac{1}{4}\ cm=1.25\ cm\\\\P=1.75+1.1+1.2+1.25=5.3\ cm[/tex]
