108k views
4 votes
(a) If the breadth of rectangle in one-third of its length and perimeter is 80 cm, find the length and breadth of rectangle. ​

User Samy Omar
by
8.1k points

2 Answers

5 votes

Answer:

width = 10, length = 30

Explanation:

the perimeter can be written as: (2 x width)(2 x length) or width + width + length + length, I'm sure there are others, but I won't get into that.

anyways, lets call width of the triangle "x". x is 1/3 of the length, in other words, x + x + x = length. we can now say that length is 3x.

width = x

length = 3x

now lets plug in these answers to the "width" and "length" in the perimeter formula

perimeter = x + x + 3x + 3x

we are given the perimeter, that is 80.

x + x + 3x + 3x = 80

x + x can be simplified to 2x

think of "x" like label, say... xylophones

2 xylophones + 3 xylophones + 3 xylophones = 8 xylophones

8x = 80

divide 80 by 8.

x = 10

now we know the width.

width = 10

remember, the length is width x 3

10 x 3 = 30

the width = 30

let's check our answer!

10 + 10 + 30 + 30 = 80

User Surazzarus
by
7.9k points
6 votes

Answer:

Length = 30m and Breadth = 10m

Step-by-step explanation:

Given that :

Perimeter = 80 m ;

Breadth = 1/3 of Length ; Length = l

We know that :

Perimeter of rectangle = 2 ( L + B ).

80 = 2 ( L + 1/3 L )

80/2 = 4/3 L.

40 = 4/3 L

3/4 × 40 = L.

3 × 10 = L.

L = 30m.

Breadth = 1/3 of Length.

Breadth = 1/3 × 30.

Breadth = 10m.

User Khadine
by
8.6k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories