Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Year | Start | Qual | Rank | Finish | Laps |
| --- | --- | --- | --- | --- | --- |
| 1938 | 33 | 113.828 | 33 | 11 | 178.0 |
| 1940 | 25 | 121.790 | 24 | 22 | 120.0 |
| 1941 | 30 | 122.951 | 17 | 15 | 173.0 |
| 1946 | 32 | 119.682 | 29 | 22 | 45.0 |
| 1947 | 18 | 128.082 | 2 | 16 | 119.0 |
| 1948 | 11 | 131.603 | 1 | 3 | 200.0 |
| 1949 | 1 | 132.939 | 1 | 29 | 23.0 |
| 1951 | 1 | 136.498 | 2 | 10 | 151.0 |
| 1952 | 4 | 136.188 | 8 | 25 | 84.0 |
| 1953 | 26 | 135.461 | 30 | 11 | 191.0 |
| Totals | Totals | Totals | Totals | Totals | 1284.0 |
Question:
How many laps did Duke Nelson complete when his qualifying time was 122.951?
Answer:
173.0