Answer:
Step-by-step explanation:

Sum of 2 perfect cubes
a³+b³=(a+b)(x²-xy+y²)
so
x³+4³=(x+4)(x²-4x+16)
set each to zero
x+4=0
x=-4
the other one can't be solveed using conventional means
use quadratic formula
for
ax^2+bx+c=0
x=

for x²-4x+16=0
x=

x=

x=

x=

x=

x=

the roots are
x=-4 and 2+2i√3 and 2-2i√3
145%
200/200: 100%
90/200= 45%
Mean=0.48
standard deviation=0.01
thus using the z-score:
P(x>0.5) we shall have the following:
z=(0.5-0.48)/0.01=2
thus
P(x>0.5)
=1-P(x<0.5)
=1-P(z<2)
=1-0.9772
=0.0228