A tea-packet measures $$10\ cm\times 6\ cm\times 4\ cm$$. How many such eta-packets can be placed in a cardboard box of dimensions $$50\ cm\times 30\ cm\times 0.2\ m$$ ?
Correct option is A. 125
Dimension of a tea packet is $$10 \space\mathrm{cm} \times 6\space \mathrm{cm} \times 4\space \mathrm{cm} $$
Volume of a tea packet $$=\text{length}\times \text{breadth} \times \text{height} =(10 \times 6 \times 4)\space \mathrm{cm}^{3}=240\space \mathrm{cm}^{3}$$
Also, it is given that the dimension of the cardboard box is $$50 \space\mathrm{cm} \times 30\space \mathrm{cm} \times 0.2\space \mathrm{m}$$ i. e., $$50\space\mathrm{cm}\times30\space\mathrm{cm}\times20\space\mathrm{cm}$$
Volume of the cardboard box $$=\text{length} \times \text{breadth} \times \text{height}=(50 \times 30 \times 20)\space \mathrm{cm}^{3}=30000 \space\mathrm{cm}^{3}$$
$$\therefore$$ The number of tea packets that can be placed inside the cardboard box $$=\frac{\text { volume of the box }}{\text { volume of a tea packet }}=\frac{30000\space\mathrm{cm^3}}{240\space\mathrm{cm^3}}=125$$