Question

the area of a rectangle and square is the ratio 3:2.if the length of rectangle is doubled and the side of square is tripled,find the ratio of their new area

Answer 1

Here is your solution


We know that Area of rectangle = length * breadth

We know that Area of square = a^2.

Now,

Given that ratio of area of rectangle and area of square is 3:2.

= > (lb)/(a^2) = 3/2. ------ (1)

(i)

Given that length of rectangle is doubled = 2l.

Area = (2l)(b) = 2lb.

(ii)

Given that Side of square is tripled = 3a.

Area of square = (3a)^2 = 9a^2.

Now,

Ratio of areas:

= > (2lb)/9a^2

= > (2/9) * (lb/a^2)

= > (2/9) * (3/2) {From (i)}

= > 1/3

= > 1 : 3

hope it helps you

Answer 2

here is your answer OK dude


If the ratio of length to breadth of a rectangle is 3:2 and its area is 38400, then find its perimeter.

Let the length be 3x and the breadth 2x. Then 3x*2x = 6x^2 = 38400,

x^2 = 38400/6 = 6400, or

x = 80. Hence the length is 80x3 = 240 units and the breadth is 80x2 = 160 units.

Therefore, the perimeter of the rectangle is 2(240+160) = 2*400 = 800 units.