Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Geometry

Question:

In the given figure, AD = 4, DE = 6, AB = 15, BF = 2, FG = 8, BC = 13, then find the ratio between Area of quadrilateral FGDE to Area of ΔABC.

Options:

\(\frac{20}{39}\)

\(\frac{50}{195}\)

\(\frac{24}{29}\)

\(\frac{31}{60}\)

Correct Answer:

\(\frac{20}{39}\)

Explanation:

Area = \(\frac{1}{2}\) × adjacent side × Sin (angle between sides)

Area of ΔEBF = \(\frac{1}{2}\) × EB × BF × Sin B 

Area of ΔEBF = \(\frac{1}{2}\) × 5 × 2 × Sin B = 5 Sin B

Area of ΔBDG = \(\frac{1}{2}\) × BD × BG × Sin B

Area of ΔBDG = \(\frac{1}{2}\) × 11 × 10 × Sin B = 55 Sin B

Area of ΔABC (P) = \(\frac{1}{2}\) × BA × BC × Sin B

Area of ΔABC (P) = \(\frac{1}{2}\) × 15 × 13 × Sin B = \(\frac{195}{2}\) Sin B

Area of quard. FGDE (Q) = Area of ΔBDG - Area of ΔBEF

                                       = 55 Sib B - 5 Sin B = 50 Sin B

Now,

⇒ \(\frac{Q}{P}\) = \(\frac{50 Sin B}{195/2 Sin B}\) = \(\frac{100}{195}\) = \(\frac{20}{39}\)