Degrees equal radians times 180 over pi. Radians equal degrees times pi over 180. π/3 radians is 60 degrees. 90 degrees is π/2 radians. The short list of formulas is in ACT Math formulas.
Cancel pi, keep the fraction
Multiply and simplify. π/6 becomes 30 degrees. 2π/3 becomes 120 degrees. If the question already used degrees in a right-triangle diagram, stay in degrees unless it asks you to convert.
Memorized values in degrees are in trig values to memorize. Cofunctions also use 90 degrees, in cofunction identities. Circle questions that stay in degrees are in circle problems.
The bottom line
Times 180/π to get degrees. Times π/180 to get radians.
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