The fraction is already in simplest form!:)
I would first convert the mixed fraction into an improper fraction. To put it lightly, the reciprocal is the numerator and denominator are switched. For this instance it would be 4/37.
Answer:
Hence, the perimeter of the triangles are:
P=123.2727 dm
P'=102.7272 dm
Step-by-step explanation:
In two similar triangles:
The ratio of the areas of two triangle is equal to the square of their perimeters.
Let A and A' represents the area of two triangles and P and P' represents their perimeter.
Then they are related as:

We are given:
A=72 dm^2 , A'=50 dm^2
and P+P'=226 dm.-----------(1)
i.e. 
on taking square root on both the side we get:

Now putting the value of P in equation (1) we obtain:

Hence,
P=226-102.7272=123.2727
Hence, the perimeter of the triangles are:
P=123.2727 dm
P'=102.7272 dm
Are you sure your in high school, also it's answer #3.