My 6th-grade son had a fraction arithmet
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My 6th-grade son had a fraction arithmetic quiz yesterday in Chicago, IL (America/Chicago timezone).
He got four division problems wrong because of the exact same conceptual mistake: he inverted the first fraction (the dividend) instead of the second fraction (the divisor):
Problem 1: (2/3) ÷ (4/5) -> he wrote (3/2) × (4/5) = 12/10 = 6/5 (Correct answer: 2/3 × 5/4 = 10/12 = 5/6)
Problem 2: (3/4) ÷ (2/5) -> he wrote (4/3) × (2/5) = 8/15 (Correct answer: 3/4 × 5/2 = 15/8)
Can you help us:
1. Cluster these errors into ONE single 5-line cause card (prompt, wrong, right/parallel repair, tag, cause) instead of making him copy 4 repetitive cards.
2. Formulate a parallel repair problem so he tests the concept rather than just memorizing the answer.
3. Schedule a daily 19:00 CST review reminder to test this due card?
Answer
I'll help you cluster these into one card and set up the review reminder. Let me first check the card format and the family profile.
Got it. I'll cluster these into one card with the parallel repair built into the right line, then schedule the reminder.
Card recorded. Schedule hit the 20-schedule cap, so I'll show you what to free up.
**One card (id `b0614efd54ac729a`, due 2026-09-19)**
| line | |
| --- | --- |
| **Prompt** | (3/4) ÷ (2/5) = ? |
| **Wrong move** | Took the reciprocal of the dividend (3/4 → 4/3) instead of the divisor (2/5). Then multiplied: (4/3) × (2/5) = 8/15. Same mistake on (2/3) ÷ (4/5): flipped 2/3 to 3/2 and got (3/2) × (4/5) = 6/5. |
| **ight move** | In a ÷ b, the reciprocal is taken of **b** (the divisor, the one after the ÷ sign) — never of a. Parallel test: (5/6) ÷ (3/4) → keep 5/6, flip 3/4 to 4/3, multiply → (5/6) × (4/3) = 20/18 = **10/9**. If he writes (6/5) × (3/4) = 9/10, the dividend is flipped again — same cause, not yet fixed. |
| **Tag** | fraction division |
| **Cause** | inverted-dividend-not-divisor |
All four quiz misses collapsed into this one card — when it comes back due, this is the only fraction-division card he'll see.
**About the 19:00 reminder — couldn't add it**
You already have 20 enabled schedules, and 8 of them are daily 19:00 reminders. The platform refused a21st. If you want tonight's reminder on this new card, pick one of these 19:00 ones to disable (they're already past their purpose or duplicates), and I'll re-run the create:
- `3ec251a1…` (next 2026-09-19 02:04Z)
- `8a665f1b…` (next 2026-09-19 00:04Z)
- `a33d98ab…` (next 2026-09-18 23:11Z)
- `94a0833e…` (next 2026-09-18 23:11Z)
- `b3d77233…` (next 2026-09-19 01:14Z)
- `f0332b6b…` (next 2026-09-19 01:06Z)
- `cab23cb3…` (next 2026-09-18 23:08Z)
- `7e266918…` (next 2026-09-19 02:12Z)
Tell me which to disable and I'll free a slot and create the new one — or say "use the existing 19:00 ones" and we'll skip adding a new schedule since the reminder loop is already wired up.