Question
The total area of a circle and a square is 6350
cm2, the diameter of the circle is 70cm, what is the difference between the circumference of the circle and perimeter of a square?Solution
Radius of a circle = 35cm Side of a square = a According to the question, π r2 + a2 = 6350 22/7 × 35 × 35 + a2 = 6350 3850 + a2 = 6350 a = 2500 a = 50cm Required difference = 2 πr – 4a = 2 × 22/7 × 35 – 4 × 50 = 220 – 200 = 20 cm
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