The Area of a Triangle
The area of a triangle can be calculated using the formula A = 1/2 * base * height, where A represents the area, base represents the length of the base of the triangle, and height represents the perpendicular distance from the base to the opposite vertex.

Given Information
In this problem, we are given that the area of the triangle is 150 cm² and the sides are in the ratio 3:4:5. Let's assume that the lengths of the sides are 3x, 4x, and 5x, respectively, where x is a positive constant.

Calculating the Area
Using the formula for the area of a triangle, we can set up the equation:
150 = 1/2 * (3x) * (4x)
Simplifying the equation, we have:
150 = 6x²
Dividing both sides by 6, we get:
x² = 25
Taking the square root of both sides, we find:
x = 5

Finding the Lengths of the Sides
Now that we know the value of x, we can find the lengths of the sides:
- The length of the first side is 3x = 3 * 5 = 15 cm.
- The length of the second side is 4x = 4 * 5 = 20 cm.
- The length of the third side is 5x = 5 * 5 = 25 cm.

Calculating the Perimeter
The perimeter of a triangle is the sum of the lengths of its sides. In this case, the perimeter is:
15 + 20 + 25 = 60 cm.

Conclusion
Therefore, the perimeter of the triangle is 60 cm.

The area of a triangle is 150cm² and its sides are in the ratio 3:4:5.what is its perimeter?