Question
If the lengths of the diameters of two concentric
circles are 16cm and 18cm respectively, then what will be the area of the region between them?Solution
Length of diameter of small circle = 16cm Radius (r) = 16/2 = 8cm Length of diameter of big circle = 18cm Radius (R) = 18/2 =9cm Area of the circle = πr² Area of the region between them = πR² - πr² =π (81-64) = 17π cm²
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