The perimeter of a triangle whose sides are in the ratio $\frac{1}{20}:\frac{1}{15}:\frac{1}{12}$ is 30 cms. The length of the biggest side is

Correct answer: $12\frac{1}{2}$

Explanation: ✅ Correct Answer: C) $12\frac{1}{2}$ 📚 Explanation: To find the ratios, multiply by the LCM of 20, 15, and 12, which is 60. The sides are in the ratio 3 : 4 : 5, which adds up to 12 parts. The total perimeter is 30, so one part is 30 / 12 = 2.5. The biggest side is 5 parts, which is 5 x 2.5 = 12.5 cms.