The dimensions of a godown are 40 m × 25 m × 10 m. If it is filled with cuboidal boxes, each of dimensions 2 m × 1.25 m × 1 m, then find the number of boxes.

Step-by-step solution

Idea: Number of boxes = volume of godown ÷ volume of one box. Here the boxes fit exactly along each side, so there is no waste.

1. Volume of godown = 40 × 25 × 10 = 10 000 m³.½ mark
2. Volume of one box = 2 × 1.25 × 1 = 2.5 m³.½ mark
3. Number of boxes = 10 000 ÷ 2.5 = 4000. Check that they fit: 40 ÷ 2 = 20, 25 ÷ 1.25 = 20, 10 ÷ 1 = 10, and 20 × 20 × 10 = 4000.1 mark

Check: Along the sides: 20 × 20 × 10 = 4000 ✓, the same as the volume method.

Answer to write in the exam

Common mistakes that cost marks

• Multiplying 2 × 1.25 × 1 wrongly as 3.25 (adding instead of multiplying).
• Dividing 10 000 by 2.5 and writing 400 (decimal-point slip).

How this can come in the exam

Try one yourself

A container is 12 m × 5 m × 4 m. How many boxes of 1.5 m × 1.25 m × 0.5 m fill it?

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