Question 926618
Use proportion comparing ON PAPER to REAL LIVE VALUE.


{{{1/72=17/R=onpaper/reallivevalue}}}.  The variable R is for the real live value of the wing span.  Solve for R.


{{{R(1/72)=(17/R)R}}}


{{{R/72=17}}}


{{{R=17*72}}}-----unit of INCHES.


You can simply use one more proportion if you want FEET instead of just INCHES.
you KNOW  12 inches is 1 foot.
{{{(17*72)/(F)=12/1}}}, using F for the amount of feet; solve for F.