In measurements related to navigation and the depth of water, one fathom is equal to approximately how many metres?

Introduction / Context:
The fathom is a unit of length traditionally used in maritime activities to measure the depth of water. Although the metric system is widely used today, older units like the fathom still appear in nautical contexts and sometimes in general knowledge questions. This problem asks the learner to recall the metric equivalent of one fathom in metres.

Given Data / Assumptions:

• The unit under discussion is the fathom.

• The question asks for the equivalent length in metres.

• Several close numerical values are given as options, making it a test of precise recall rather than rough estimation.

• The learner is expected to know the relation between feet and metres as well.

Concept / Approach:
By definition, one fathom equals six feet. In the metric system, one foot equals 0.3048 metre. Therefore, one fathom in metres is obtained by multiplying six by 0.3048. This conversion allows a direct calculation of the correct metric value. If a candidate remembers either the exact conversion or the commonly used rounded value, the answer can be identified correctly among the options.

Step-by-Step Solution:
Step 1: Start from the definition of a fathom: 1 fathom = 6 feet. Step 2: Recall the standard conversion factor between feet and metres: 1 foot = 0.3048 metre. Step 3: Multiply 6 by 0.3048 to obtain the length of one fathom in metres. Step 4: Compute 6 * 0.3048 = 1.8288. Step 5: Look at the options and choose 1.8288 metres as the correct value.

Verification / Alternative check:
The conversion factor 1 foot = 0.3048 metre is an internationally accepted exact definition. Multiplying this value by 6 gives 1.8288 metres exactly. Nautical tables and standard unit conversion references confirm that one fathom equals 1.8288 metres. Even if someone only remembers that one fathom is approximately 1.83 metres, this is close enough to match the option 1.8288 metres confidently.

Why Other Options Are Wrong:
Values like 1.7699 metres and 2.0210 metres are deliberately close distractors but do not match the exact multiplication result. The number 2.1212 metres is even farther from the exact value. The option 1.5000 metres would correspond to about 4.92 feet, which is not equal to six feet. None of these alternate values correctly represents six feet converted to metres, so they are all incorrect for one fathom.

Common Pitfalls:
A common mistake is to confuse the number of feet in a yard with a fathom. One yard is three feet, while one fathom is six feet, exactly double. Another pitfall is to round too early during conversion and then pick an option that is close but not exact. To avoid errors in competitive exams, it is better to memorise a few key exact relationships, such as 1 foot = 0.3048 metre and 1 fathom = 1.8288 metres.

Final Answer:
One fathom is equal to approximately 1.8288 metres.