Question

a hollow garden roller, 56cm wide with base area 154cm square, is made of 4cm thick iron. find the volume of the iron

Answer 1

Given,
Width of roller (h) = 56 cm
Base area = 154 cm2
Thickness of iron sheet = 4 cm
Inner radius = r  
 Outer Radius = R = r + 4

Volume of Iron = Volume of roller with outer radius (R) - Volume of radius with inner radius (r)

Volume of Iron = 22/7 R2h - 22/7 r2h = 22/7 h (R2 - r2)
                       
Base Area = 22/7 R2

154 cm2 = 22/7 R2
154 cm2 / 22/7 = R2
49 cm2 = R2
Therefore,
R = 7 cm

Since, R = r + 4
Therefore, 
7 = r + 4
r = 3 cm

Therefore, By formula of Volume of Iron 
Volume = 22/7 h (R2 - r2)
             = 22/7 * 56 cm [(7 cm)2 - (3 cm)2]
             = 22 * 8 cm (49 cm2 - 9 cm2)
             = 22 * 8 cm * 40 cm2
             = 22 * 320 cm3
             = 7040 cm3

Therefore, The Volume of Iron = 7040 cm3

Answer 2

Step-by-step explanation:

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