Subject: General Aptitude · Chapter: Area · Exam: 2006 · Marks: · Difficulty:
The areas of two similar triangles are $12 \mathrm{cm}^{2}$ and $48 \mathrm{cm}^{2}$. If the height of the smaller one is 2.1 cm, then the corresponding height of the bigger one is
(a)0.525 cm
(b)4.2 cm
(c)4.41 cm
(d)8.4 cm
Answer
Answer (as printed): B
Explanation
Note : The areas of two similar triangles are in the ratio of the squares of the corresponding altitudes. Let the length of the required altitude be $x$ cm. Then, $\frac{12}{48}=\frac{(2.1)^{2}}{x^{2}} \Rightarrow x^{2}=(4.41 \times 4) \Rightarrow x=2.1 \times 2=4.2 \mathrm{cm}$.