Two per day supply new finite data or a transfer question at the same target. They extend a lesson or reteach one misconception; they are not extra formal assessments. Day 5 and Day 10 swaps are after-check only. All numbers are invented and independently recalculated in the verifier.
| Day | Worked swap 1 · prompt → answer | Worked swap 2 · prompt → answer |
|---|---|---|
| 1 | Gallery: 12 choose sculpture, 9 painting, 3 both. Distinct participants? → 12+9−3=18; both are counted once. |
App test: 10 choose text, 8 sound, 2 both. At least one? → 10+8−2=16. |
| 2 | 14 choose sketching, 11 weaving, 20 at least one. Both? → 14+11−20=5; if total 25, neither 5. |
9 choose puzzles, 7 music, 12 at least one. Both? → 9+7−12=4; if total 15, neither 3. |
| 3 | Three sets 8,7,6; pairs 3,2,2; triple 1. Union? → 8+7+6−3−2−2+1=15; each pair includes centre. |
Three sets 10,9,8; pairs 4,3,3; triple 1. Union? → 10+9+8−4−3−3+1=18. |
| 4 | One of five craft or two outdoor sessions, no shared option. Count? → 5+2=7 bookings. |
One of four local or six online talks, no overlap. Count? → 4+6=10, not 24 pairs. |
| 5 | After G: sets 8 and 7 with overlap 2, universe 17. Union/neither? → 13 in at least one and 4 neither. | After G: three indoor or two outdoor bookings, one only. Count? → 3+2=5. |
| 6 | Four badge shapes and three captions, all pairs allowed. Count? → 4×3=12. |
Two routes and five times, every pairing allowed. Count? → 2×5=10. |
| 7 | Branch A: 3×2; branch B: 1×4; one branch only. Count? → 6+4=10. |
Branch A: 2×4; branch B: 3×2; one branch only. Count? → 8+6=14. |
| 8 | Seven exact regions: A only 3, B only 2, C only 1, AB only 2, AC only 1, BC only 1, all 1. Union? → 11; A=7, B=6, C=4, pair counts 3/2/2; formula returns 11. | An alleged triple count is 2 but AB pair count is 1. Possible? → No; all-three is a subset of AB, so pair must be at least 2. |
| 9 | Two-set story 11 and 8 with 3 both; a disjoint choice of 2 or 5. Methods/results? → Overlap: 16; disjoint addition: 7. | Two-stage label 3×3; exclusive branches 2×2 or 1×5. Results? → Product 9; branches 4+5=9. |
| 10 | After H/I: sets 9,8,7; pairs 3,3,2; triple 1. Union? → 9+8+7−3−3−2+1=17. |
After H/I: exclusive routes 2×3 and 3×2. Count? → 6+6=12; each product is a different branch. |
An instructor changes a surface context only after checking set totals, pair/triple consistency and the meaning of an outcome. Do not use a near-identical solved swap to coach a fresh check before its first response.