Five numbers, three darts each, doubles only to finish: ladder #239 asks for 4, 46, 71, 96 and 104.
4 is a straight double: D2. If the dart lands in the single by mistake you are left on 2, which still has a double finish with the darts you have left. 46 is a two-dart finish: 6 D20.
71 is a two-dart finish: T17 D10. 96 is a two-dart finish: T20 D18. 104 is a two-dart finish: T18 Bull.
One route here finishes on the bull (T18 Bull for 104); it counts as a double.
At best the five finishes need 9 darts out of 15. Your result counts the finishes you make first and the darts you used second. These are friendly numbers. Aim at the inside half of the double on the first dart — a miss on that side lands in the single and keeps the finish alive.