Q17 of 32 Page 13

A reservoir in the form of a rectangular parallelopiped is 20 m long. If 18 kl of water is removed from the reservoir, the water level goes down by 15 cm. Find the width of the reservoir.

Let the width of the reservoir = x m
Volume of water flowing from the reservoir = l × b × h
                                                       = 20 × x × 0.15
                                                       = 3x m3
                  Volume of the water removed = 18 m3 (1m3 = 1000 litre)
                  Hence 3x = 18 ⇒  x = 6m
∴ Width of the reservoir = 6m

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