Question

Using the concept of significant figures, match Column I with the correct number of significant figures in Column II.
$\begin{array}{cccc}& \text{Column I}& & \text{Column II}\\ i& 0.1234& \text{a.}& 5\\ ii& 1.2100\text{cm}& \text{b.}& 4\\ iii& 47.23÷2.3& \text{c.}& 1\\ iv& 3\times {10}^8& \text{d.}& 2\end{array}$

• A. $i–b;ii–a;iii–d;iv–c$
• B. $i–b;ii–a;iii–c;iv–d$
• C. $i–b;ii–d;iii–a;iv–c$
• D. $i–c;ii–a;iii–d;iv–b$

Answer 1

The correct option is A $i–b;ii–a;iii–d;iv–c$

For $\left(i\right)$:
Number of significant figures: 4
Only digits after decimal are considered.

For $\left(ii\right)$:
Number of significant figures: 5
Zeroes after decimal are significant, but zeroes before decimal are not.

For $\left(iii\right)$:
Number of significant figures: 2
When operations like multiplication or division are used, the significant figures of the answer should be equal to least significant figures in any of the numbers.

For $\left(iv\right)$:
Number of significant figures: 1
The order of 10 of the number is insignificant.