Question

from a rectangular piece of metal sheet of length and breadth 1.60 m and 80 cm respectively 3 circular sheets of 20 cm radius are cut out what area of metal is left

Answer 1

Length of the metal sheet=1.60m=160cm

Breadth of the metal sheet=80cm

Total area of the metal sheet=l*b
=160*80
=12800$cm^{3}$


Radius of each circle=20cm

Circumference of circle=$\pi r^{2}$
=$\pi * 20^{2}$
=22/7*400
=8800/7$cm^{2}$

Circumference of 3 circles=8800/7*3
=26400/7
=3771.42$cm^{2}$(approx.)

Area of metal sheet left= total area of metal sheet-circumference of three circles
=(12800-3771.42)$cm^{2}$
=9028.58$cm^{2}$(approx.)


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