Question

The perimeter of the sector whose radius is 14 cm and angle at the centre
45then
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Answer 1

Let us consider a circle with radius 7 cm.

We can find its circumference by simple formula 2×π×r. In our case, r=7. Hence we get,

C=2×π×7= 2×22/7×7 =2×22 =44.

Now, a circle is 360°. If I want to find the length of the arc of a sector of angle 45°, we devide C by 8. We get,

C÷8=44÷8=5.5

This is the length of the arc. Now, to get complete perimeter, we add the radius 2 times. Hence we get,

5.5+2×r=5.5+2×7=5.5+14=19.5

This is the perimeter of the sector of the circle with radius 7 and angle 45°.

I hope this helps.