The average age of 10 members of a committee is the same as it was 4 years ago, because an old member has been replaced by a young member. Find how much younger is the new member ?
When a clock is observed, the hour hand is at a minute mark and the minutes hand is six minutes ahead of it.
When the clock is observed again after some time, the hour hand is precisely on a different minute mark and the minute hand is seven minutes ahead of it.
Can you calculate how much time has elapsed between the two observations?