An elevator descends into mine shaft at the rate of 5 meter per minute.
so for 1 min elevator descends 5metres.
the position of the elevator after one hour =
we know 1 hour =60 min so 60min x 5metres=300 meters..
but the elevator began to descend from 15 meters above so,
and its position after 45 mins is 45metres x 5 mins=225 meters.
and the elevator has descended from 15 meters above so
hope this helps u.