Question

A steel tape is used to measure a plot of land 90 mx 35 m . In me
error for length and breadth is + 2 cm , Determine the standard er
a) 0.93 m
b) +2.02 m²
c) +1.93 m²
d) +1.75 m²​

Answer 1

Given info : A steel tape is used to measure a plot of land 90 mx 35 m . In standard error for length and breadth is ± 2 cm

To find : the standard error in area of steel tape.

solution : using formula,

$e_A=\sqrt{\left(e_l\frac{dA}{dl}\right)^2+\left(e_b\frac{dA}{db}\right)^2}$

where $e_A$ is standard error in area.

$e_l$ is standard error in length.

$e_b$ is standard error in breadth.

here dA/dl = 90 m , dA/db = 35 m, el = eb = ±2 cm = ±0.02 m

⇒ eA = √{(0.02 × 90)² + (0.02 × 35)²}

= √{(1.8)² + (0.7)²}

= 1.93 m²

Therefore standard error in area of steel tape is 1.93 m².

Answer 2

Answer:

Therefore standard error in area of steel tape is 1.93 m².