Subject: General Aptitude · Chapter: Volume and Surface Area · Exam: · Marks: · Difficulty:
Shobhraj takes a cube of 1 m edge-length and meticulously cuts smaller cubes, each of edge-length 1 mm from the parent cube. He joins these small cubes end-to-end. Thus, the total length of this 'cube-robe' will be
(a)1 km
(b)10 km
(c)100 km
(d)1000 km
Answer
Answer (as printed): D
Explanation
Number of cubes formed $=\frac{10^{3} \times 10^{3} \times 10^{3}}{1 \times 1 \times 1}=10^{9}$. $$\begin{aligned} \therefore & \text { Total length of cube-robe }=\left(1 \times 10^{9}\right) \mathrm{mm}=10^{9} \mathrm{mm} \\ & =\left(\frac{10^{9}}{10^{6}}\right) \mathrm{km}=10^{3} \mathrm{km}=1000 \mathrm{km} . \end{aligned}$$