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A Subterfuge After All (Brain Teaser)

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A Subterfuge After All

Q. Now, we may have to go back to our school days to solve this drum problem.

One Mr. Sita Ram was dealing in mobile oil. There were some big drums in his godown containing mobile oil and all the drums were of same size. His servant used to open the locked drums for issuing oil to the customers. One day the servant did not turn up and locks could not be opened for delivery. The customers arrived for oil. Sita Ram decided to make holes at the bottom and drain off oil for issue.

One servant Ramu drilled a 6 cm semi-circular hole one drum. Another servant Khaldu drilled three holes of 5 cm each in another drum.

If the quantity of oil is the same in both the drums and if the oil is taken out from both the drums simultaneously, which drum would empty first?

A. Ramu’s drum was emptied before Khaldu’s.
Note: Liquid flow-out (qty. coming out) depends on the area of the hole it is passing out through. 6 cm. half circular hole-area is  x 62 that is 36 sq. cm.
Circumference of three 5 cm holes is equal to:
, 52 x 52 x 3= 75.4, which is definitely smaller than the area created by hole made by Ramu.