Answer:
15cm
Step-by-step explanation:
Let x be the arc circumference.
The circumference of a circle usually subtends to 360°, that is, one complete revolution is 360°.
#Given the arc angle as 45° and the circumference as 120cm, the arc circumference can be obtained as:
#Apply proportions to find x:
[tex]360\textdegree=120cm\\45\textdegree=x\\\\x=(120/360)\times 45\\\\x=15cm[/tex]
Hence, the arc circumference is 15cm