Q 11-01-039NEETJEE MainEasy
Three lengths $16.2\ \text{m}$, $0.847\ \text{m}$ and $3.08\ \text{m}$ are added. The sum, with due regard to significant figures, is
Answer: (D) $20.1\ \text{m}$
Actual sum $= 16.2 + 0.847 + 3.08 = 20.127\ \text{m}$
In addition and subtraction, the rule is about decimal places, not significant figures. The least precise value, $16.2$, has one decimal place, so the result is rounded to one decimal place:
$$20.1\ \text{m}$$
Solution by Sreeraj P, M.Sc Physics