Question

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

• A. $111\pi /540$
• B. $121\pi /540$
• C. $131\pi /540$
• D. $128\pi /541$

Answer 1

Answer: (B)

We know that $180^{\circ }=\pi$ radian
Hence $40^{\circ }20^{\prime }=40\frac{1}{3}$ degree $=\frac{121\pi }{540}$ radian
Therefore $40^{\circ }20^{\prime }=\frac{121\pi }{540}$ radian.