Can you check my work please?

Celia is staring at the clock waiting for school to end so that she can go to track practice. She notices that the 4-inch-long minute hand is rotating around the clock and marking off time like degrees on a unit circle.

Part 1: How many radians does the minute hand move from 1:25 to 1:50? (Hint: Find the number of degrees per minute first.)

My Answer: Part one:
(360degrees/60minutes = 6 degrees per minute.)
1:25 to 1:50 is 25 minutes. 25 x 6 = 150.
150pi/180 = 5pi/6,

Respuesta :

Your answer is correct. Indeed:

- In order to find the degrees per minute, you have to divide the full rotation angle (which is 360deg) by the number of minutes (which is 60):
360deg ÷ 60min = 6 deg/min

- In order to find how many minutes have passed, you subtract the times:
1h50m - 1h25m = 0h25m

- You then find how many degrees correspond to 25minutes:
6 deg/min × 25 min = 150deg

- Lastly, you transform degrees into radiants, through the proportion:
deg : 180 = rad : π
Therefore,
150 : 180 = rad : π
rad = (150×π)/180 = 5π/6