Two triangles, ΔPRS and ΔDEF, are similar, whose perimeters are 36 cm and 40 cm, respectively. If the length of DE is 10 cm, then what is the length (in cm) of PR?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 9.
PR/DE = (Perimeter of ΔPRS)/(Perimeter of ΔDEF)
⇒ PR/10 = 36/40 = 9/10
⇒ PR = 10 × (9/10) = 9 cm