According to a plan, a drilling team had to drill to a depth of 270 meters below the ground level. For the first three days the team drilled as per the plan. How ever, subsequently finding that their resources were getting underutilized according to the plan, it started to drill 8 metres more than the plan every day. Therefore , a day before the planned date they had drilled to a depth of 280 metres. How many metres of drilling was the plan for each day.