Which of the following are the cubes of odd numbers?
Question:

Which of the following are the cubes of odd numbers?

(i) 125

(ii) 343

(iii) 1728

(iv) 4096

(v) 9261

Solution:

The cube of an odd number is an odd number. Therefore, 125, 343 and 9261 are the cubes of odd numbers.

$125=5 \times 5 \times 5=5^{3}$

$343=7 \times 7 \times 7=7^{3}$

$9261=3 \times 3 \times 3 \times 7 \times 7 \times 7=3^{3} \times 7^{3}=21^{3}$