I need help with this bc i dont understand it can somebody help me plzzzzz i'll give you 40 points for it!!!! And name you brainly!!!!!!!

Answer:
8.79 in
Step-by-step explanation:
23 = 150/360 × 2×3.14× r
23 = 5/12 × 6.28 x r
23 = 31.4×r / 12
31.4 r = 23×12
31.4 r = 276
r = 276/31.4
r = 8.79 in