Subject
Quantitative Aptitude
Topic
Areas & Volumes
A hollow iron pipe is 21 cm long and its external diameter is 8 cm. If the thickness of the pipe is 1 cm and iron weighs 8 g/cm3, then the weight of the pipe is:
A hollow iron pipe is 21 cm long and its external diameter is 8 cm. If the thickness of the pipe is 1 cm and iron weighs 8 g/cm3, then the weight of the pipe is:
ক)
3.6 kgখ)
3.696 kgগ)
36 kgঘ)
36.9 kgExplanation
External radius = 4 cm, Internal radius = 3 cm. Volume of iron = (22/7 x ((4)2 – (3)2) x 21 ) cm3 = (22/7 x 7 x 1 x 21) cm3 = 462 cm3 So, Weight of iron = (462 x 8) gm = 3696 gm = 3.696 kg.Related questions
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