According gto 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, susequently finding that their resources were getting underutilised 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.
A)38 meters
B)30 meters
C)27 meters
D)None of these

• equn formed - (3x+5(x+8)=280)
  
  ans - b. 30m
• 10 years agoHelpfull: Yes(5) No(5)
• each drilling metre = x
  days to be drilled= y
  so,xy=270 {given}
  
  now,
  3x+(x+8)(y-4)= 280 { 3x why? bz for 3 days drilling is according to the old plan ,no changes, so days multiplied by drilling meter ;
  (x+8) why? bz its given in question now every day the drillling meter increases by 8 metre;
  (y-4) why? bz total days in starting we have taken y, 3 days got used drilling metre as it is,plus one before work got completed,so it becomes y- 3-1=y-4;
  (x+8)(y-4) got multiplied i.e meter *no.of days}
  
  8y-x=42 { by using above two equations}
  
  now,substitute y=270/x from 1st equation
  
  x^2+42x-2160=0
  x=30;
  or u can direct substitute value of y in terms of x n get the same ans
• 8 years agoHelpfull: Yes(4) No(0)