angleslice/360 times area=area of slice
area=pir^2
normally pizzas are given in terms of ther diameter
so 10=diameter
d/2=r, 10/2=5
r=5
area=pi5^2=25pi
angleslize/360 times 25pi=15
do math
times 360 both sides and divide by 25pi both sides
angle=68.7549 degrees or 1.2 radians
