- A22
- B33
- C44
- D121
Step-by-Step Solution
Take one factor from each triple: (check: ). Answering 121 keeps instead of a single 11 — each triple contributes exactly one factor, never two.
Answer: A) 22
By prime factorisation, . What is ?
Class 8Cubes and Cube RootsCubes and Roots
Key idea: Cube root by prime factorisation
**Step 1**: factorise into primes.
**Step 2**: group the prime factors into TRIPLES (three of the same).
**Step 3**: take ONE factor from each triple — their product is the cube root.
Example: ∛216. . So ∛216 = 6.
Example: ∛13824. . So ∛13824 = 24.
If any prime doesn't form a complete triple, the number isn't a perfect cube.
**Step 2**: group the prime factors into TRIPLES (three of the same).
**Step 3**: take ONE factor from each triple — their product is the cube root.
Example: ∛216. . So ∛216 = 6.
Example: ∛13824. . So ∛13824 = 24.
If any prime doesn't form a complete triple, the number isn't a perfect cube.
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