InterviewSolution
Saved Bookmarks
| 1. |
ΔABC and ΔPQR are similar to each other. If the ratio of area of ΔABC and ΔPQR is 1 ∶ 16, and the length of side AC is 28 cm, then find the length of PR.1. 156 cm2. 96 cm3. 100 cm4. 112 cm |
|
Answer» Correct Answer - Option 4 : 112 cm Given: ΔABC and ΔPQR are similar to each other. Ratio of area of ΔABC and ΔPQR = 1 : 16 Length of side AC = 28 cm Concept: Relation among areas, side of similar triangles ABC and PQR (Area of ΔABC and ΔPQR) = (AB/PQ)2 = (BC/QR)2 = (AC/PR)2 Calculation: Let PR be x cm (Area of ΔABC and ΔPQR) = (AC/PR)2 ⇒ (1/16) = (28/x)2 Taking square root on both the sides ⇒ √(1/16) = √(28/x)2 ⇒ (1/4) = (28/x) ⇒ x = 28 × 4 ⇒ x = 112 cm ∴ The length of PR is 112 cm. |
|