Question

The ratio of the side lengths of a triangle is 3:4:5, and it’s perimeter is 72cm . What is the length of the longest side of the triangle?

Answer 1

let; sides be 3x, 4x and 5x.

according to the question,

perimeter=72 cm

now,

perimeter=sum of each sides

72=3x +4x + 5x

72=12x

x=72 / 12

x=6 cm

then,

longest side of triangle= 5x

5x=5*6

=30 cm.

Answer 2

• Let the sides be 3x, 4x and 5x.
• Therefore, 3x + 4x + 5x = 72
• or, 12x = 72
• or, x = 6
• So, the length of the longest side of the triangle = (5 × 6) cm = 30 cm.

Answer:

30 cm

Hope you could understand.

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