5 + 1 Dual Chamber Number Picker (70/25): How to use this preset
What the selection means
The 70/25 preset uses five numbers from 1–70 and one from 1–25. It differs from the 69/26 preset in both pool sizes, so check that your activity lists contain exactly 70 and 25 entries. A number in one chamber does not remove its counterpart from the other.
Using the controls
Choose the number of sets and a tumble time, then press Pick Numbers. Read the main and secondary results separately. Switching between selection order and sorted order changes the display, not which balls were picked. Each new set refills both chambers.
An activity to try
Build a story exercise with 70 numbered subject cards and 25 setting cards. The five main picks become elements to include in the story; the secondary pick supplies its setting. Decide together how to connect the elements. For a different number of subjects or settings, recreate the two pools in Custom Preset.
Create your own version with PhysPicks
Set the number range and pick count for each chamber to build a two-part game, such as prompts and instructions.
Create a dual-chamber gameWhat are the probabilities?
These calculations assume uniform selection without replacement within each pool and independent chambers. They describe a mathematical model, not measured or certified probabilities for the PhysPicks physics simulation.
| Event defined before the selection | Theoretical probability |
|---|---|
| One specified main number is the first ball out | 1/70 ≈ 1.43% |
| One specified main number appears anywhere in the completed set | 5/70 ≈ 7.14% |
| Exactly one of your 5 preselected main numbers matches (secondary pool ignored) | 3,385,200/12,103,014 ≈ 27.97% |
| One specified secondary number appears in the secondary selection | 1/25 ≈ 4% |
| One specified complete combination, ignoring order | 1/302,575,350 |
C(70,5) × C(25,1) = 302,575,350
For k picks from n numbers, a specified number is included with probability k/n. There are C(n,k) = n! / (k!(n−k)!) unordered sets. With two independent pools, multiply their combination counts. “One specified number appears” is different from “exactly one of my chosen numbers matches”. A previous result does not make a number due next time.
P(X = 1) = C(5,1) × C(65,4) / C(70,5)