1331/216 का घनमूल है:

Quantitative Aptitude ·Previously asked in HP Patwari 2019

View the full solved paper: HP Patwari 2019

Question

1331/216 का घनमूल है:

  1. A. 6/7
  2. B. –7/4
  3. C. 11/6 (Correct answer)
  4. D. इनमें से कोई नहीं

Correct Answer

Option C — 11/6

Detailed Solution & Explanation

The correct answer is 11/6.

Key Points

  • 1331 = 11³ and 216 = 6³.
  • So the cube root of 1331/216 = 11/6.

Additional Information

  • Rule: ∛(a/b) = ∛a / ∛b — take the cube root of numerator and denominator separately.
  • Cubes worth memorising: 1³=1, 2³=8, 3³=27, 4³=64, 5³=125, 6³=216, 7³=343, 8³=512, 9³=729, 10³=1000, 11³=1331, 12³=1728.
  • Shortcut for spotting a cube root: the last digit of the cube fixes the last digit of the root — a cube ending in 1 has a root ending in 1, ending in 8 → root ends in 2, ending in 7 → root ends in 3.