11. A retangular field is 15 m long and 10 m wide. Another rectangular field having the same
perimeter has its sides in the ratio 4 : 1. Find the dimension of the rectangular field.
Answers
Step-by-step explanation:
ANSWER
Let width of path x
Length =20+2x
Width =14+2x
Area of outer rectangular =l×b
=(20+2x)(14+2x)
=4x
2
+68x+280
Area of path:
4x
2
+68x+280−280=111
4x
2
+68x=111
4x
2
+68x−111=0
(4x
2
+74x−6x−111)=0
(2x−3)(2x+37)=0
x=
2
3
m or x=−
2
37
Since, width can not be −ve
Hence, the width is 1.5 m
A rectangular field is 15 m long and 10 m wide. Another rectangular field having the same perimeter has its sides in the ratio 4:1. Find the dimension of the rectangular field.
- A rectangular field is 15 m long and 10 m wide.
- The other rectangular field having the same perimeter has its sides in the ratio 4:1.
The dimension of the other rectangular field.
Length of the field = 15 m
Width of the field = 10 m
Perimeter
= 2(Length+Width) m
= 2(15+10) m
= 2×25 m
= 50 m
Perimeter of both the fields are equal.
So, perimeter of the other field = 50 m
Ratio = 4:1
Let its length and width are 4a m and a m respectively.
According to condition,
2(4a+a) = 50
➳ 2×5a = 50
➳ 10a = 50
Divide both sides by 10.
➳ 10a÷10 = 50÷10
➳ x = 5
a = 5
Length = 4a m = (4×5) m = 20 m
Width = a m = 5 m
The length and width of the other field are 20 m and 5 m respectively.
2(4a+a) = 50
➳ 2(20+5) = 50
➳ 2×25 = 50
➳ 50 = 50
So, L.H.S = R.H.S.
Hence, verified.