::
One way to calculate this is to adjust the debt weighting
formula:
w_e = E / (D + E) = E/E / (D/E + E/E) = 1 / (0.7 + 1) = 0.59
Sometimes the easiest way to solve problems like this is to
put in fake numbers. If D/E = 0.7, then we could set D = 7 and E = 10. The
equity weight would then be 10 / (10 + 7) = 0.59.