a boy wants to make cuboids of dimensions 5m,6m,7m from small cubes of .03m 3.later he realizes he can make same cuboids by making it hollow.then it takes some cubes less.what is the number of the cubes to be removed?

• it's simple....
  just calculate 5*6*7 = 210 then divided by 0.03 so we get 7000
  then calculate (5-2)*(6-2)*(7-2) = 60 then divided by 0.03 so we get 2000
  finally 7000-2000=5000.
  5000 cubes to be removed..
  
• 12 years agoHelpfull: Yes(12) No(2)
• solved by admin..........
  only ctrl+c & v by me........:)
  volume of the small cube = 0.03 m^3
  so side of this cube = cubic root of 0.03 m^3 = .312 m
  so after removing the outermost layer the dimensions for the inner cuboid will be (5-2*0.312), (6-2*0.312), (7-2*0.312)
  so total volume will be (4.376)*(5.376)*(6.376) = 150 m^3
  so no of cubes will be 150/0.03 = 5000
  so we can remove 5000 inner cubes
  
• 12 years agoHelpfull: Yes(11) No(4)
• @lovejeet singh: because the boy is making cuboids hollow...and to make any cuboid hollow we have to remove edges of both the sides..
• 12 years agoHelpfull: Yes(2) No(1)
• @MANIBHARATHI: Why we have subtracted 2 from each side...!!!
  plzz let me know !!!!
  Thx in advance !!
• 12 years agoHelpfull: Yes(1) No(0)