Question

When $24.25\times {10}^3$ is rounded off to three significant figures, it becomes :

• A. 242
• B. 243
• C. $244\times {10}^2$
• D. $24.2\times {10}^3$

Answer 1

Answer: (D)

$24.2\times {10}^3$

$24.25\times {10}^3\to 2,4,2,5\to$ present by it has 4 significant digits.
If the digit to be dropped is 5 or 5 followed by zeros, then preceding digit is left unchanged, if it is even.
So, up to three significant figures, the number $=24.2\times {10}^3$