JEE Main 2026 — 23 January, Morning Shift — Question 29

$\ell_{\text {mean }}=\frac{\ell_{1}+\ell_{2}+\ell_{3}+\ell_{4}}{4}$ $\ell_{\text {mean }}=\frac{20.00+19.75+17.01+18.25}{4}$ $=18.75$ $\Delta \ell_{\text {mean }}=\frac{\left|\Delta \ell_{1}\right|+\left|\Delta \ell_{2}\right|+\left|\Delta \ell_{3}\right|+\left|\Delta \ell_{4}\right|}{4}$ $=\frac{1.25+1+1.74+0.5}{4}=1.12$ So, relative error $=\frac{\Delta \ell_{\text {mean }}}{\ell_{\text {mean }}}=\frac{1.12}{18.75}=0.06$