Find the length and breadth of a rectangle given that its perimeter is 840 cm and length is four times its breadth.
Answers
Answered by
10
Hi !
Let the breadth , "b''---> be "x"
Length = l = 4x
We know that,
perimeter = 2( l + b)
840 cm = 2( 4x + x)
10x = 840
x = 84 cm
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Breadth = 84 cm
Length = 4x = 336 cm
rimikhan:
Dear answer will be 84cm is right but 2nd answer is 340 cm
no , u can verify the ans with the conditions given
Ok
2(84 +336) = 2*420 = 840 cm
Ohh thank you so much.
:)
Answered by
5
Hey there!!
_______________________________________
For Perimeter = 2(l+b)---------(1)
Now, let the breadth be = x
So ,according to the question , the length = 4x .
Now perimeter given = 840cm. ----(2)
Equating (1) and (2):
☞2(l+b) = 840
Now, by substituting the values of length and breadth we have :
☞ 2 (4x+x ) = 840
=> 2(5x) = 840
=> 10x = 840
=> x= 84 .
Hence breadth is 84 cm
Now length = 4x= 4*84 =336 cm.
_____________________________
________________
# hope the answer helps you!
_______________________________________
For Perimeter = 2(l+b)---------(1)
Now, let the breadth be = x
So ,according to the question , the length = 4x .
Now perimeter given = 840cm. ----(2)
Equating (1) and (2):
☞2(l+b) = 840
Now, by substituting the values of length and breadth we have :
☞ 2 (4x+x ) = 840
=> 2(5x) = 840
=> 10x = 840
=> x= 84 .
Hence breadth is 84 cm
Now length = 4x= 4*84 =336 cm.
_____________________________
________________
# hope the answer helps you!
But answer will be 85 cm, 340 cm
Maybe! The answer is given wrong dear! Because the answer I'm getting satisfies the question demand!
Yeah! I'm too getting the same answer! Or else Recheck the question again !!!!!
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