Question

the sides of a triangular plot are in ratio of 3 ratio 5 ratio 7 and its perimeter is 300 find its area

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Answer 1

Step-by-step explanation:

Let the common multiple be x

Therefore, the sides will be 3x & 4x & 5x

3x + 4x + 5x = 300

12x = 300

x = 300/12

x = 25

Therefore,

First side = 3x = 3×25 = 75 cm

Second side = 5x = 5×25 = 125 cm

Third side = 7x = 7×25 = 175 cm

Now find area

Answer 2

Let the sides of the triangle be 3x, 5x and 7x repsectively and since the perimeter is 300m

So, 3x + 5x + 7x=300

15x=300

x=300/15

x=20 m

so,length of one side=60 m

length of second side=100 m

and length of third side=140 m

Now perimeter=300m

therefore semi-perimeter=150 metre

now according to herons formula -

Area = root 150* (150-60) * (150-100) * (150-140)

= root 150 * 90 * 50 * 10

= root 30*5 * 30*3 * 5*10 *10

= root 30^2 * 5^2 * 10^2 *3

= 30 * 5 * 10 * root 3

= 1500 root 3