Question

length of a rectangle is found to be 12.4cm find value of area and error in determination in area​

Answer 1

$\huge\star{\tt{\underline{\underline{\red{Answer\implies2cm^{2}}}}}}\star$

Answer 2

$\huge\star{\tt{\underline{\underline{Answer:2cm^{2}}}}}\star$

Area=l x b

= 12.4 x 8

= 99

∆$\frac{A}{A}$ =∆$\frac{l}{l}$ = ∆$\frac{b}{b}$___________(1)

$\implies$ ∆$\frac{A}{b}$ +∆$\frac{l}{l}$ = ∆$\frac{b}{b}$

∆A=lxb(∆$\frac{l}{l}$ + ∆$\frac{b}{b}$

∆A =∆lb+∆bl

= 12.4 x 0.1+8.0 x 0.1

=1.24 +0.8

≈2cm²