Question

Convert ${40}^{\circ }{20}^{\prime }$ into radian measure.

• A. $\frac{121}{540}\pi$ radians
• B. $\frac{121}{570}\pi$ radians
• C. $\frac{120}{513}\pi$ radians
• D. None

Answer 1

The correct option is A $\frac{121}{540}\pi$ radians

Given: ${40}^0$${20}^{{}^{\prime }}$

${40}^0+\frac{{20}^0}{{60}^0}$

$=40+\frac{1^o}{3}=\frac{{121}^0}{3}$

$radian=\frac{\pi }{{180}^o}\times \frac{{121}^o}{3}$

$=\frac{121}{540}\pi radians$