suppose that D+E=A, that N/A=.25 and that D/A=0.15. Solve for N/E.
this one takes some "playing around"
I did this
D+E=A, divide each term by A
D/A + E/A = A/A
0.15 + E/A = 1
E/A = .85 = 85/100 = 17/20
Then A/E = 20/17
But N/E = (N/A)(A/E) = (25/100)(20/17)
= 5/17 or appr. .294