Question

In the figure above $\Delta ABC\sim \Delta KLM$. What is the perimeter of $\Delta ABC$ ?
(Note: All lengths are given in centimeters. The symbol $\sim$ means "is similar to.")

• A. $12$
• B. $14$
• C. $21\frac{1}{2}$
• D. $35$
• E. $71\frac{3}{4}$

Answer 1

The correct option is B $14$

Since the triangles are similar, hence $\frac{AC}{KM}=\frac{BC}{LM}=\frac{AB}{KL}$.
Therefore $\frac{3}{7.5}=\frac{BC}{15}=\frac{AB}{12.5}$

$\Rightarrow BC=6$ and $AB=5$
$\Rightarrow AB+AC+BC=5+3+6=14$