The length, width, and height of a box are 12 cm, 18 cm, and 36 cm respectively. Which of the following sized cubes can be packed in this box without leaving gaps? (a) 9 cm (b) 6 cm (c) 4 cm (d) 3 cm (e) 2 cm
Explanation
For a cube of side 's' to fit perfectly in a box of dimensions × 36, 's' must be a common factor of 12, 18, and 36. Finding HCF: 12 = 2² × 3, 18 = ², 36 = 2² × 3². HCF = = 6. So the largest cube that fits has side 6 cm. Any factor of 6 will also work. Factors of 6 are: 1, 2, 3, 6. From the options: 9 cm (not a factor of 12), 6 cm (works), 4 cm (not a factor of 18), 3 cm (works), 2 cm (works).
Solution Steps
Step 1: Find HCF of 12, 18, and 36.
Step 2: HCF = 6, so 6 cm cubes fit perfectly.
Step 3: Any factor of 6 will also work: 1, 2, 3, 6.
Step 4: Check each option: 9 (no), 6 (yes), 4 (no), 3 (yes), 2 (yes).