Question 1015306
N+D+Q=108

D=(N/3)+8

Q=2D

Since Q=2D, D+Q= 3D so go to D=(N/3)+8 and triple it. 

3D=N+24 

and 

N+N+24 = 108

2N= 84

N=42

Since 3D = N+24

3D= 66, and D=22

Q= 108-42-22= 44

N=42, D=22, Q=44

Check and see the numbers solve for each of the original criteria.