Answer: The required value of 'w' is 5 units.
Step-by-step explanation: We are given the following formula:
[tex]P=2l+2w~~~~~~~~~~~~~~~~~~~~~~~(i)[/tex]
We are given to find 'w' in units given that P = 30 units and l = 10 units.
Substituting the values of 'P' and 'l' in equation (i), we get
[tex]P=2l+2w\\\\\Rightarrow 30=2\times 10+2\times w\\\\\Rightarrow 30=20+2w\\\\\Rightarrow 2w=10\\\\\Rightarrow w=5.[/tex]
Thus, the required value of 'w' is 5 units.