Question

The length of a 27 square metre field is three times in its breadth .what is approximately times it will take to walk all the four sides of its boundary at the rateof 2 kilometre per hour

Answer 1

Answer : 12 hours

Solution :
__________

Given that : The length is three times as its breadth.

Let, Breadth = x then Length = 3x

Also given that : Area of rectangle = 27 m²

According to the question :

$3x \times x = 27 \\ \\ = > 3 { {x}^{2} } = 27 \\ \\ = > {x}^{2} = 9 \\ \\ = > x = 3$

So, Breadth will be x = 3 m and

Length = 3x = 3×3 = 9 m

As we know that : Perimeter of rectangle

$2(l + b) \\ \\ = > 2(9 + 3) \\ \\ = > 2 \times 12 \\ \\ = > 24 \: m$

Given that : It takes 1 hour to walk two kilometers.

$Then ,\: in \: 1 \: km \: \: it \: takes \: = \frac{1}{2} hour \\ \\ = > 24 \: km \: = \frac{1}{2} \times 24 = 12 \: hours$

So, it will take 12 hours to walk all four sides of boundary.