Question

hollow cylindrical pipe is 21 m long kurta and inner diameters are 10 cm and 6
cm respectively​

Answer 1

Answer:

Step-by-step explanation:

here ,

h= 21m or 210cm  

so,

inner volume =

\pi {r}^{2} h \\  =  \frac{22}{7}  \times 3 \times 3 \times 210 \\  = 22 \times 270 \\  = 5940 {cm}^{3}  \\  

outer volume =

\pi {r}^{2} h \\  =  \frac{22}{7}  \times 5 \times 5 \times 210 \\  = 22 \times 750 \\  = 16500 {cm}^{3}  

volume of metal used=

(16500 - 5940) {cm}^{3}  \\  = 10560 {cm}^{3}  

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