import math

def area_coberta(r, n):
    return (n*r**2)/2 * math.sin(2*math.pi/n)

def perc_area(perc):
    l = []
    n = 4
    area_cercle = math.pi*1.0**2
    tpc = 100 * (area_coberta(1,n))/area_cercle
    t = (n,round(tpc,4))
    l.append(t)
    while tpc < perc:
        n = n + 2
        tpc = 100 * (area_coberta(1,n))/area_cercle
        t = (n,round(tpc,4))
        l.append(t)
        if len(l) > 3:
            l = l[1:]
    return l