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Probability

Question
CBSEENMA9003538

Rain water which falls on a flat rectangular surface of length 6 cm and breadth 4 m is transferred into a cylindrical vessel of internal radius 20 cm. What will be the height of water in the cylindrical vessel if the rain fall is 1 cm? Give your answer to the nearest whole number. (Use straight pi = 3.14)

Solution
Volume of rain water
equals 6 cross times 4 cross times 1 over 100 space straight m cubed
equals space 6 over 25 space straight m cubed

Let the height of water in the cylindrical vessel be h cm, Then,
Volume of water in the cylindrical vessel = π(20)2 h cm3 According to the question,
6 over 25 cross times 100 cross times 100 cross times 100 equals 3.14 cross times 400 cross times h
rightwards double arrow space space space space space space space space space straight h equals 191 space cm

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