Question

Que. एक कपड़े का क्रय मूल्य 35 रुपये है। यदि उस कपड़े की लम्बाई 4 मीटर अधिक होती है और प्रत्येक मीटर का मूल्य 1 रुपये कम होता, तो कुल क्रय मूल्य अपरिवर्तित रहता। कपडे की लम्बाई कितनी थी?​

Answer 1

Answer:

Length of cloth will be 10

Answer 2

Answer:

10 meter

Step-by-step explanation:

Let x be the length ( in meters ) of the cloth,

Given,

Cost price of the cloth = 35 rupees,

So, the original price per meter = $\frac{35}{x}$

After increasing the length by 4 meters,

New price per meter = $\frac{35}{x+4}$

Now, according to the question,

$\frac{35}{x}-1=\frac{35}{x+4}$

$\frac{35-x}{x}=\frac{35}{x+4}$

By cross multiplication,

$(x+4)(35-x)=35x$

$35x-x^2+140-4x=35x$

$x^2+4x-140=0$

By middle term splitting,

$x^2+14x-10x-140=0$

$x(x+14)-10(x+14)=0$

$(x+14)(x-10)=0$

$\implies x=-14\text{ or }x=10$

∵ Length can not be negative,

Hence, the length of the cloth is 10 meters.