Suppose that A = D + E and that D/A = 0.80. Solve for D/E.

Question

These are the steps I have taken, but I don't know how to proceed.

1. Divide A = D + E by A.
2. 1 = .80 + E/A
3. .20 = E/A
4. A/A = 1, D/A = .80, E/A = .20.

Answer 1

given: D/A = .8 = 8/10 = 4/5
5D = 4A
A = 5D/4

from A = D + E, since we want D/E, why not divide the equation by E to create the D/E in your equation ?

A/E = D/E + 1
(5D/4)/E = D/E + 1
5D/(4E) - 4D/(4E) = 1
D/(4E) = 1
D/E = 4

Answer 2

A+D=