Respuesta :

In 30 minutes the minute hand makes half a turn around the clock, so it sweeps half a circle.

Given the radius [tex] r [/tex], the area of a circle is [tex] A = \pi r^2 [/tex]

In this case, we're interested in half the area of a circle with radius 14cm, so we have

[tex] A^* = \dfrac{\pi \cdot 14^2}{2} = \dfrac{196\pi}{2} = 98\pi [/tex] cm squared.
we know that the area of circle is A(circle)=(pie)r^2
and when the minute hand of a wall clock move for 30mn, we get a semicircle, yeild A(semicircle)=(pie)r^2(1/2). substitute all the known values we get, A(semicircle)= 307.72 cm^2

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