A body travels uniformly a distance of  $(13.8 \pm 0.2) m$in a time $(4.0\pm 0.3)$ s. The velocity of the body within error limits is

Here, $S=(13.8\pm 0.2)m$

 and $t=(4.0\pm 0.3)sec$

 Expressing it in percentage error, we have,

$S=13.8\pm \frac{0.2}{13.8}\times 100\%=13.8\pm 1.4\%$

 and $t=4.0\pm \frac{0.3}{4}\times 100\%=4\pm 7.5\%$

 $\because V=\frac{s}{t}=\frac{13.8\pm 1.4}{4\pm 7.5}=(3.45\pm 0.3) m/s$