Question

The length and breadth of a rectangular field are in the ratio 4:3 of the area of the field is 4800m2 then find the cost of fencing at ₹80 per m

Answer 1

Given

→Ratio of length and breadth of a rectangular field= 4:3

$→area \: of \: field = {(4800)m}^{2}$

→ The cost of fencing = ₹80 per metre.

Solution

Let the common ratio be x .

so length=4x

breadth=3x

Area of rectangle = Length×Breadth

$→\:we\:have\: area \: of \: field = {(4800)m}^{2}$

→4x × 3x = 4800

${(12)x}^{2} = 4800$

${x}^{2} = \frac{400}{12}$

${x}^{2} = 400$

$x = \sqrt{400}$

$x = 20$

Now,

Length = 4 x 20 = 80m

Breadth= 3x 20 = 60m

●To find the rate of fencing ,we need to find its perimeter first.

→Perimeter means sum of all the sides .

Perimeter of rectangle =2×(length+breadth)

Perimeter = 2 x (80 + 60) m

= 2 x 140

= 280m

Rate of fencing = ₹ 80 per m (given)

If 1 metre = ₹ 80

then,

For 280 m = 280 × 80

= ₹ 22400

Total cost of fencing the field = ₹ 22400

Answer 2

→Ratio of length and breadth of a rectangular field= 4:3

→$area \: of \: field = {(4800)m}^{2}$

→ The cost of fencing = ₹80 per metre.

Solution :-

Let the common ratio be x .

so length=4x

breadth=3x

Area of rectangle = Length×Breadth

→$we\:have\:area\:of\:field=(4800)m 2$

→$4x × 3x = 4800 (12)x 2 =4800$

${x}^{2} = \frac{400}{12} x 2 = 12400$

x=20

Now,

Length = 4 x 20 = 80m

Breadth= 3x 20 = 60m

●To find the rate of fencing ,we need to find its perimeter first.

→Perimeter means sum of all the sides .

Perimeter of rectangle =2×(length+breadth)

Perimeter = 2 x (80 + 60) m

= 2 x 140

= 280m

Rate of fencing = ₹ 80 per m (given)

If 1 metre = ₹ 80

then,

For 280 m = 280 × 80

= ₹ 22400

Total cost of fencing the field = ₹ 22400