In the given figure, ABCD is a square. EFGH is a square formed by pointing the mid points of sides of ABCD. LMNO is a square formed by joining the mid points of sides of EFGH. A circle is inscribed inside LMNO. If area of circle is 38.5 cm2, then what is the area (in cm2) square ABCD?
In the given figure, ABCD is a square. EFGH is a square formed by pointing the mid points of sides of ABCD. LMNO is a square formed by joining the mid points of sides of EFGH. A circle is inscribed inside LMNO. If area of circle is 38.5 cm2, then what is the area (in cm2) square ABCD? Correct Answer 196
Given Area of circle = 38.5
⇒ 22/7r2 = 38.5
⇒ r2 = 12.25
⇒ r = 3.5 cm
⇒ Side of square LMNO = 2 × 3.5 = 7 cm
In ΔNHO, suppose NH = OH = a
Now applying Pythagoras theorem in ΔNHO,
⇒ a2 + a2 = 49
⇒ a = 7/√2
⇒ NH = OH = 7/√2
⇒ Side of square EFGH = 2 × 7/√2 = 7√2 cm
In ΔFDH, suppose FD = DH = b cm
Now applying Pythagoras theorem in ΔFDH,
⇒ b2 + b2 = 98
⇒ b = 7 cm
⇒ FD = DH = 7 cm
⇒ Side of square ABCD = 2 × 7 = 14 cm
∴ Area of square ABCD = 196 cm2
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Feb 20, 2025