In measuring the side of a square, an error of $5%$ in excess is made. The error $%$ in the calculated area is,

In measuring the side of a square, an error of $5%$ in excess is made. The error $%$ in the calculated area is,

1). $10 \frac{1}{4} % $
2). $ 10 \frac{3}{4} % $
3). $1 \frac{3}{4} % $
4). $25%$

100 cm is read as 105 cm

 A₁ = (100 x 100) cm² and A₂ = (105 x 105) cm²

⇒ (A₂ - A₁) = [(105)² - (100)²]

⇒ (A₂ - A₁) = (105 + 100) x (105 - 100)

⇒ (A₂ - A₁) = 205 × 5 cm²

⇒ (A₂ - A₁) = 1025 cm²

∴ Percentage error = (change in area/ original area) x 100

(1025/10000) x 100 = 10.25% = 10¼ % 

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