MCQ
By what number should $81$ be divided to get a perfect cube?
- A$6$
- ✓$3$
- C$9$
- D$7$
✓
Answer
Correct option: B.
$3$
The prime factorisation of $81$ will be:
$81 = 3 \times 3 \times 3 \times 3$
$81 = 3^3 \times 3$
Hence, we need to divide $81$ by $3$ to get:
$\frac{81}{3}=27=3^3$
$81 = 3 \times 3 \times 3 \times 3$
$81 = 3^3 \times 3$
Hence, we need to divide $81$ by $3$ to get:
$\frac{81}{3}=27=3^3$
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