Math, asked by rimikhan, 1 year ago

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 Anonymous

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

------------------------------------------------------------

Breadth = 84 cm
Length = 4x = 336 cm

rimikhan: Dear answer will be 84cm is right but 2nd answer is 340 cm

Anonymous: no , u can verify the ans with the conditions given

rimikhan: Ok

Anonymous: 2(84 +336) = 2*420 = 840 cm

rimikhan: Ohh thank you so much.

Anonymous: :)

Answered by Hannah10301

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!

rimikhan: But answer will be 85 cm, 340 cm

Anonymous: Maybe! The answer is given wrong dear! Because the answer I'm getting satisfies the question demand!

Hannah10301: Yeah! I'm too getting the same answer! Or else Recheck the question again !!!!!

Previous Question

Next Question