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प्रश्न
The radii of two concentric circles are 19 cm and 16 cm respectively. The area of the ring enclosed by these circles is
पर्याय
320 cm2
330 cm2
332 cm2
340 cm2
उत्तर
330 cm2
Let ;
R = 19 cm and r = 16 cm
Thus, we have ;
Area of the ring = π(R2 - r2)
= π (R + r) (R - r)
`= |22/7xx(19+16)xx(19-16)|"cm"^2`
`=(22/7xx35xx3)"cm"^2`
= 330 cm2
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