Question

A rectangular plate has length (4 ± 0.04) cm and width (2 ± 0.02) cm. The maximum percentage error in the measurement of its area is –

• A. 2%
• B. 6%
• C. 3%
• D. 4%

Answer 1

Answer: (B)

6%

Answer 2

$\frac{\Delta A}{A}$× 100 = $\frac{\Delta\mathcal{l}}{\mathcal{l}}$× 100 + $\frac{\Delta b}{b}$× 100

= $\frac{0.04}{4}$× 100 + $\frac{0.02}{2}$× 100

= 6%