Checkout ladder #226 climbs from 24 to 118 in five steps — 24, 56, 63, 84 and 118 — with three darts per finish and a double to end on.
24 is a straight double: D12. If the dart lands in the single by mistake you are left on 12, which still has a double finish with the darts you have left. 56 is a two-dart finish: 16 D20.
63 is a two-dart finish: T17 D6. 84 is a two-dart finish: T20 D12. 118 needs all three darts: T20 18 D20. If the first dart misses its treble, the board will show the new route straight away.
At best the five finishes need 10 darts out of 15. Your result counts the finishes you make first and the darts you used second. The last finish is long. Throw the first dart at the big treble with intent, then let the board work out what is left.