Subject: General Aptitude · Chapter: Area · Exam: · Marks: · Difficulty:
A farmer wishes to start a 100 sq. m rectangular vegetable garden. Since he has only 30 m barbed wire, he fences three sides of the garden letting his house compound wall act as the fourth side fencing. The dimension of the garden is:
(a)15 m × 6.67 m
(b)20 m × 5 m
(c)30 m × 3.33 m
(d)40 m × 2.5 m
Answer
Answer (as printed):
Explanation
We have : $2 b+l=30 \Rightarrow l=30-2 b$. Area $=100 \mathrm{m}^{2} \Rightarrow l \times b=100 \Rightarrow b(30-2 b)=100$ $\Rightarrow b^{2}-15 b+50=0$ $\Rightarrow(b-10)(b-5)=0$ $\Rightarrow b=10$ or $b=5$. When $b=10, l=10$ and when $b=5, l=20$. Since the garden is rectangular, so its dimension is $20 \mathrm{m} \times 5 \mathrm{m}$.