A boy wants to make cuboids of dimension 5m, 6m and 7m from small cubes of .03 m3. Later he realized 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?
a) 2000 b) 5000 c) 3000 d) 7000

• volume of solid cube=5*6*7=210
  no. of small cubes required for solid cube=210/0.03=7000
  volume of hollow cube=(5-1)*(6-1)*(7-1)=4*5*6=120
  no. of small cubes required for hollow cube=120/0.03=4000
  no. of cubes to be removed=7000-4000=3000
  
• 8 years agoHelpfull: Yes(8) No(4)
• 5*6*7=210
  (5-1)(6-1)(7-1)=120
  d=210-120=90
  no of cube=90/.03
  =3000
• 8 years agoHelpfull: Yes(1) No(1)
• 0.3^(1/3)=0.7 approx
  (4.3*5.3*6.3)/.03=5000
• 8 years agoHelpfull: Yes(1) No(2)
• 27+27+21+21+9+9=114
• 8 years agoHelpfull: Yes(0) No(2)
• (5-0.03*2)*(6-0.03*2)*(7-0.03*2)/0.03=nearly 7000
• 8 years agoHelpfull: Yes(0) No(1)
• Total volume of cube = 5 * 6 * 7 = 210 m cube
  volume of smaller cube 0.03
  Total cubes reqd = 7000
  for hollow cube no. of
  small cubes reqd = 5/0.03 *4 + 6/.03 * 4 + 7/0.03 *4 which is approx 2000
  so 5000 cubes have to be removed
  
• 8 years agoHelpfull: Yes(0) No(1)