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beyond the control – поза контролем;
under the same conditions – за однакових умов;
length – довжина;
to obey the laws – дотримуватись законів;

mathematical laws of probability – математичні закони
ймовірності.

Task 2. Read and translate the following text

Text 2 Types of Surveying Errors

Accuracy, precision and error have specific meanings in the
context of surveying. Accuracy is a measure of reliability. In other

words:
Accuracy = True value – Most probable value where the ‘most
probable value’ is derived from a set of measurements.
Errors always exist in measurements, where:

The error (E) = Actual true value – Estimate of that true
value. If the estimate is a bad one, then the error will be large.
Accuracy and precision are usually quoted as a ratio, or as parts

per million, e.g. 1:100 000 or 10 ppm, or in units of the quantity
measured, e.g. 0.03 m.
Of these three concepts, accuracy, precision and error, only
precision may be numerically defined from appropriate computations

with the observations. Accuracy and error may be assumed,
sometimes erroneously, from the precision but they will never be
known for sure.

Ordinary errors in surveying, met in all classes of survey work,
may be classified as:
1. mistakes.

2. accidental errors.
3. systematic or cumulative errors.
4. compensating errors.

Mistakes in surveying are errors which arise from inattention,
inexperience, carelessness and poor judgment or confusion in the
mind of the observer. They do not follow any mathematical rule (law
of probability) and may be large or small, positive or negative. They

cannot be measured. However, they can be detected by repeating the
whole operation. If a mistake is undetected, it produces a serious
effect upon the final result. Hence, every value to be recorded in the

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