Question

Find the value of $\tan {25}^{\circ }{15}^{\prime }$

Answer 1

	$0^{\prime }$	$6^{\prime }$	${12}^{\prime }$	${18}^{\prime }$	${24}^{\prime }$	${30}^{\prime }$	${36}^{\prime }$	${42}^{\prime }$	${48}^{\prime }$	${54}^{\prime }$	Mean Diff.
	${0.0}^{\circ }$	${0.1}^{\circ }$	${0.2}^{\circ }$	${0.3}^{\circ }$	${0.4}^{\circ }$	${0.5}^{\circ }$	${0.6}^{\circ }$	${0.7}^{\circ }$	${0.8}^{\circ }$	${0.9}^{\circ }$	$12345$
${25}^{\circ }$		$0.4706$									$11$

Write ${25}^{\circ }{15}^{\prime }={25}^{\circ }{12}^{\prime }+3^{\prime }$. From the table
$\tan {25}^{\circ }{12}^{\prime }=0.4706$
Mean Difference for $3^{\prime }=0.0011$
$\therefore \tan {25}^{\circ }{15}^{\prime }=0.4706+0.011=0.4717$