Answer:
Option 3rd is correct that is 24 cm.
Explanation:
We have been given the shortest side of the triangle which is 12 centimeters.
We have been given the ratio of the three sides of the triangle
let the unknown side of the triangle be x
So, according to the ratio given we will have sides as:
2x : 3x :4x
since, shortest side is 12
So, 2x=12
x=6
Now, we have to find the longest side which is 4x
So, the required side is: 4 x 6 =24 centimeters
Therefore, option 3rd is correct.