Question

Length of a rectangular park is $50\text{m}$ and width is $10\text{m}$. If length of the park is decreased by $20\text{m}$ then what will be change in perimeter of the park?

• A. $40\text{m}$
• B. $50\text{m}$
• C. $60\text{m}$
• D. $120\text{m}$

Answer 1

The correct option is A $40\text{m}$

We know, perimeter of any shape is the sum of all of its sides.
as this is the rectangular park so,

Perimeter$=50+10+50+10$
Perimeter$=120\text{m}$

Now, length of the park is decreased by $20\text{m}$Perimeter of the park with changed length $=30+10+30+10=80\text{m}$

Change in the perimeter of the park on changing length of the park is $120-80=40\text{m}$