Ok call your first number x.
The second number is x+8.
The third number is 2x.
Add them. 2x +x +8+x =100
Combine like terms. 4x +8 =100
Subtract 8 from both sides 4x =92
X (your first number) is 23
Your second number (x +8) is 31
Tour third number (2x) is 46
