Piyush365
  • 1

A cube of side 5 cm is painted on all its faces. If it is sliced into 1 cm³ cubes, how many of these 1 cm³ cubes have: (i) exactly three faces painted? (ii) exactly two faces painted? (iii) exactly one face painted? (iv) no face painted?

  • 1

For a 5 cm cube sliced into unit cubes: 8 corner cubes have three faces painted, 12 × 3 = 36 edge cubes have two, 6 × 9 = 54 face-center cubes have one and 3³ = 27 interior cubes have none.

Cbse Class 9 Maths Ganita Manjari Part 2 Solutions
Class 9 maths ganita manjari part 2 chapter 14 question answer

Share

1 Answer

  1. For n = 5 unit segments per edge:

    Three painted faces occur at the 8 corners, giving 8 cubes.

    Two painted faces lie along the 12 edges, excluding corners, giving 12(n – 2) = 12 × 3 = 36 cubes.

    One painted face lies on the interior of the 6 faces, giving 6(n – 2)² = 6 × 9 = 54 cubes.

    Unpainted cubes form the inner core, calculated as (n – 2)³ = 3³ = 27 cubes.

     

    For more NCERT Solutions of Class 9 Maths Ganita Manjari Part 2 Chapter 14 Math of Space: Surface Area and Volume Question Answer (2026-27)

    https://www.tiwariacademy.com/ncert-solutions/class-9/maths/ganita-manjari-chapter-14/

    • 3
Leave an answer

Leave an answer

Browse