Given:
Perimeter of a parallelogram = 64 cm
Length = 3 times larger than the width
To find:
The length of the parallelogram.
Solution:
We know that, the perimeter of the parallelogram is:

Where, l is length and w is width of the parallelogram.
We have, l = 3w and P=64.
So,



Divide both sides by 8.

Now,



Therefore, the length of the parallelogram is 24 cm.