Question

9)Find the perimeter of a semicircular plate of radius 3.85 cm.
10. If the perimeter of semicircular protractor is 108 cm, then find the diameter of the
- protractor.
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Answer 1

Answer:

9) 19.8cm

10)21cm

Step-by-step explanation:

9) Perimeter of semi circle is pi*r = pi*3.18 = 12.1

We have to add diameter to get total perimeter of disc = 7.70

Total perimeter = 19.8cm

10) Use same formula to get equation

pi*r+ 2r= 108.

Solve using pi as 22/7