Answer:45.9
Explanation:
Circumference=12
Length of arc=8/5=1.6
π=3.14
Circumference=2 x π x r
12=2x3.14xr
12=6.28 x r
Divide both sides by 6.28
12/6.28=(6.28 x r)/6.28
2=r
r=2
Length of arc =Φ/360 x 2 x π x r
1.6=Φ/360 x 2 x 3.14 x 2
1.6=(Φ x 2 x 3.14 x2)/360
1.6=12.56Φ/360
Cross multiply
1.6x360=12.56Φ
576=12.56Φ
Divide both sides by 12.56
576/12.56=12.56Φ/12.56
45.9=Φ
Φ=45.9