Water is filled in a container in such a manner that its volume doubles after every five minutes. If it takes 30 minutes for the container to be full, in how much time will it be one-fourth full?
(a) 7 minutes and 30 seconds (b) 10 minutes (c) 20 minutes (d) 25 minutes
(c) Container is filled in 30 min.
∴ Container is half-filled in (30 – 5) = 25 min
Hence, time taken for the container to be one-fourth
filled = (25 – 5) = 20 min.
