Basic Units – One fathom is equal to how much length?

Introduction / Context:
Nautical measurements frequently use the unit “fathom,” especially for water depth and anchor cables. Knowing the exact equivalence in feet and metres helps convert readings on charts or in maritime reports into familiar units.

Given Data / Assumptions:

• Definition needed: 1 fathom = ?
• Common conversions: 1 foot = 30.48 cm; 1 m = 100 cm.
• We compare against feet, metres, and centimetres options.

Concept / Approach:
By definition, 1 fathom equals 6 feet. Converting to metric: 6 ft * 30.48 cm/ft = 182.88 cm = 1.8288 m. Recognizing this standard avoids confusion with tens-based guesses.

Step-by-Step Solution:
Start with the standard: 1 fathom = 6 feet.Optional metric check: 6 * 0.3048 m = 1.8288 m.Compare with choices: only “6 feet” matches definition.

Verification / Alternative check:
Maritime chain lengths and depth soundings are often given in fathoms; sailors historically used armspan approximations close to 6 feet, which aligns with the formal definition.

Why Other Options Are Wrong:

• 6 meters: far too large (≈ 19.7 ft).
• 60 feet: an order of magnitude off.
• 100 cm: equals 1 m, not 1.8288 m.

Common Pitfalls:
Assuming a metric-friendly value due to base-10 familiarity; “fathom” is historical and fixed at 6 feet, not 10 or 100 of anything.

Final Answer:
6 feet