Question 157309
{{{D+N+Q=197}}} Start with the first equation



{{{(1/3)N+2+N+3D=197}}} Plug in {{{D=(1/3)N+2}}} and {{{Q=3D}}}



{{{(1/3)N+2+N+3((1/3)N+2)=197}}} Plug in {{{D=(1/3)N+2}}}



{{{(1/3)N+2+N+3((1/3)N)+3(2)=197}}} Distribute



{{{(1/3)N+2+N+N+6=197}}} Multiply



{{{(1/3)N+2N+8=197}}} Combine like terms.



{{{N+6N+24=591}}} Multiply <b>EVERY</b> term by the LCD 3 to clear out the fractions.



{{{7N+24=591}}} Combine like terms.



From here you have a simple linear equation. Once you have N, plug this into the second equation to get D. Finally, plug D into the third equation to get Q.  Let me know if you need any further help. 



Note: you should get D=29, N=81, and Q=87 as an answer.