13. Four mark exercise problems V

1. Guna has fixed a single door of width \(3 \ feet\) in his room where as Nathan has fixed a double door, each of width \(1 \frac{1}{2} \ ft\) in his room. From the closed position, if each of the single and double doors can open up to \(120^{\circ}\), whose door takes a minimum area?

 

Answer:

2. In a rectangular field which measures \(15 \ m \times 8 \ m\), cows are tied with a rope of length \(3 \ m\) at four corners of the field and also at the centre. Find the area of the field where no cows can graze. \(\pi = 3.14\)

 

Answer:

 

Area of the field \(=\)  \(m^2\)

 

(Note: Round off the answer to \(2\) decimal places.)