All Exams Test series for 1 year @ ₹349 only
Question

The length of a rectangular pitch is 30 m more than its breadth. Its area is $18,271$ m$^{2}$. Its breadth (in m) is:

The correct answer is
121

Solving for Rectangular Pitch Breadth

This solution explains how to find the breadth of a rectangular pitch given its area and the relationship between its length and breadth.

Understanding the Problem

We are given a rectangular pitch with the following information:

  • The length ($l$) is 30 m more than its breadth ($b$). This can be written as: $l = b + 30$
  • The area ($A$) of the pitch is $18,271$ m$^2$.
  • We need to find the breadth ($b$) of the pitch in meters.

Setting Up the Equation

The formula for the area of a rectangle is:

$A = \text{length} \times \text{breadth}$

Substituting the given values and the relationship between length and breadth:

$18,271 = (b + 30) \times b$

Solving the Quadratic Equation

Expanding the equation, we get:

$18,271 = b^2 + 30b$

Rearranging this into the standard quadratic equation form ($ax^2 + bx + c = 0$):

$b^2 + 30b - 18,271 = 0$

We can solve this quadratic equation for '$b$' using the quadratic formula:

$b = \frac{-B \pm \sqrt{B^2 - 4AC}}{2A}$

In our equation, $A=1$, $B=30$, and $C=-18,271$. Plugging these values into the formula:

$b = \frac{-30 \pm \sqrt{30^2 - 4(1)(-18,271)}}{2(1)}$

$b = \frac{-30 \pm \sqrt{900 + 73,084}}{2}$

$b = \frac{-30 \pm \sqrt{73,984}}{2}$

To find the value of $\sqrt{73,984}$: $\sqrt{73,984} = 272$

Now, substitute this back into the equation for '$b$':

$b = \frac{-30 \pm 272}{2}$

Determining the Breadth

We have two possible solutions for '$b$':

  1. $b = \frac{-30 + 272}{2} = \frac{242}{2} = 121$
  2. $b = \frac{-30 - 272}{2} = \frac{-302}{2} = -151$

Since the breadth of a rectangle must be a positive value, we discard the negative solution.

Therefore, the breadth ($b$) of the rectangular pitch is 121 m.

Verification

If the breadth is 121 m, then the length is:

$l = b + 30 = 121 + 30 = 151$ m

The area calculated using these dimensions is:

$A = l \times b = 151 \times 121 = 18,271$ m$^2$

This matches the given area, confirming our calculation.

Final Answer

The breadth of the rectangular pitch is 121 m.

Was this answer helpful?

Important Questions from 2-D Mensuration

  1. The sides of a rectangular field are 169 m and 154 m long. Its area is equal to the area of a circular field. What is the circumference (in m) of the circular field? Take $\pi = \frac{22}{7}$
  2. Find the area of a sector with a central angle of 150° in a circle with a radius of 12 cm.
  3. The area of a square is $2304$ cm$^2$. Its perimeter is equal to the perimeter of a regular hexagon. What is the area (in cm$^2$) of the hexagon?
  4. Calculate the area of the triangle whose sides are 8 cm, 9 cm and 13 cm. (Rounded up to two decimal places)

  5. In a circle of radius 10.5 cm, if the angle of a sector is $\frac{2\pi}{3}$, then the perimeter of the sector is (in cm):
    (Take $\pi = \frac{22}{7}$)
Need Expert Advice?

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App