<PRE><B>Question 1105622</B>
If the cost of making a leather ball is Rs. 431.20 at  Rs. 17.50 per square cm. Let us write by calculating the length  of diameter of the ball.
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Number of square centimeters = 431.2/17.5 = 24.64
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Surface Area = 4*pi*r^2
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Solve for &quot;r&quot;&quot;:
4pi*r^2 = 24.64
r = 1.96 cm
Ans: Diameter = 2*1.96 = 3.92 cm
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Cheers,
Stan H.
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