If abcde=1 (where a,b,c,d and e are all positive real numbers) then what is the minimum value of a+b+c+d+e?

using A.M > = G.M

(a+b+c+d+e) / 5 >= [abcde]^(1/5)

== a+b+c+d+e >= 5

1x1x1x1x1=1 1+-1+1+-1+1+-1=0 thus a+b+c+d+e=0 maximum

minimum=-1

If a + b + c = 8 a.b.c = 27 then Is there exist solution/s in (a,b,c) where a, b and c are positive real numbers?