-12 I just did this question In class
C=x+9, c+x=99, c=99-x
So we have two equations equal to c, c=x+9 and c=99-x, since c=c:
x+9=99-x
2x+9=99
2x=90
x=45, and since c=x+9, c=54
So Charlie weighs 54 kg and his brother weighs 45 kg.
Answer:
V≈33.51
although I don't have an explanation, sorry, if you look up "how to find the volume of a sphere" on google, it will give you the answer
