A standard multiple tube fermentation test is run on a sample of water from a surface stream. The result of the analysis for the confirmed test are shown below:
| Size of sample (ml) | Number of negative result for MPN test. |
| 10 | 0 |
| 1 | 0 |
| 0.1 | 1 |
| 0.01 | 2 |
| 0.001 | 3 |
|
Combination of positive (10 ml-1 ml-0.1 ml) |
\(MPN \space index\over100ml\) |
| 4-3-2 | 39 |
| 5-4-3 | 280 |
| 5-5-4 | 1600 |
| 0-0-1 | 4800 |
| 0-1-2 | 600 |
| 1-2-3 | 72 |
Most Probable number of the sample is?
Enter numerical value using the virtual keypad. Round off where necessary.