Answer:
Step-by-step explanation:x+y+z=100(let x ,y,z represent the first second and third numbers respectively)
Therefore,y=2z
z=x-8
y=2x-16
substituting the values of x,y and z into the question,we have
x+(2x-16)+(x-8)=100
Simplifying,we have
4x-24=100
adding 24 to both sides of the equation,
4x=100+24
4x=124
dividing both sides of the equation by the co-efficient of x,we have
4x/4=124/4
4.31=124
therefore,x=31.