Ok, so if the angle is 120 degrees, its one third of the full cake (which is 360 degrees). So the area of the whole circle (worked out with area = pi * r^2 where r is 30) gives 900*pi, and so one third of that (because her slice is one third) is 300pi.
Answer: 8
Step-by-step explanation: Speed is distance/time
18/3 = 6 miles per hour running
18/2 = 9 miles per hour biking
3 hour bike = 27 miles
1.50 hour run (0.50 because 30 minutes is half of an hour) = 9 miles
27 + 9/3 + 1.50 = 36/4.5 or 8
0.666667 as a fraction is 2/3