Multiplication Trick for 3‑Digit Numbers with a Zero in the Middle

Overview

A short vertical animation (9:16) that demonstrates a fast mental‑math trick for multiplying two three‑digit numbers that each contain a zero in the middle, e.g. $203 \times 507$. The viewer sees the numbers stacked, each intermediate calculation highlighted in electric blue, yellow, and pink, and the final product assembled in under 20 seconds.

---

Phases

#	Phase Name	Duration	Description
1	Intro	~2s	Dark charcoal background fades in. The two numbers $203$ (top) and $507$ (bottom) appear vertically centered in electric blue, spaced for readability.
2	Step 1 – Right Digits	~3s	Highlight the rightmost digits (3 and 7) in yellow. Show the multiplication $3\times7=21$ appearing directly below the highlighted pair in electric blue, then fade the highlight.
3	Step 2 – Left Digits	~3s	Highlight the leftmost digits (2 and 5) in yellow. Display $2\times5=10$ appearing to the left of the previously shown “21” in electric blue, then fade the highlight.
4	Step 3 – Cross‑multiply	~5s	Draw two diagonal lines: one from the 2 (top left) to the 7 (bottom right) and another from the 5 (top middle) to the 3 (bottom left). While the lines are drawn, show the calculations $2\times7=14$ and $5\times3=15$ in pink beside each line. Then place the sum $14+15=29$ a short distance below the cross‑product lines (centered horizontally between the “10” and “21” blocks) so it does not overlap any previously displayed numbers. The sum appears in pink.
5	Assemble Result	~4s	Morph the three pieces (“10”, “29”, “21”) together to form the final answer $102921$ in electric blue, centered where the original numbers were. A brief glow emphasizes the completed product.
6	Outro	~2s	Fade out the final answer while a small caption "#MathHack" in yellow appears at the bottom, then fade to black.

---

Layout

┌───────────────────────────────────────┐
│               TOP AREA                 │
│          CRAZY MATH HACK               │
├───────────────────────────────────────┤
│               MAIN AREA                │
│   Numbers stacked vertically, centered │
│   All intermediate steps appear here   │
├───────────────────────────────────────┤
│               BOTTOM AREA              │
│   Small caption / hashtag (optional)   │
└───────────────────────────────────────┘

Area Descriptions

Area	Content	Notes
Top	Text “CRAZY MATH HACK” (large, bold)	Fades in during Intro, remains visible through all steps, disappears by Outro
Main	Stacked numbers $203$ over $507$ and all animated calculations (right‑digit product, left‑digit product, cross‑products, sum, final answer)	Primary focus; uses electric blue for numbers, yellow for highlights, pink for cross‑product sum
Bottom	Small caption or hashtag (e.g., “#MathHack”)	Appears in Outro, small font, yellow

---

Notes

• Color palette: Background charcoal (#222222). Numbers and final answer electric blue (#00ffff). Highlights (digit selection) yellow (#ffea00). Cross‑product calculations pink (#ff69b4).
• Pacing: All animations are snappy (ease‑in‑out with ~0.3 s for each highlight/move) to keep total runtime ~19 s.
• Mobile readability: Font sizes chosen large enough for vertical phone screens; spacing ensures no overlap.
• Transitions: Simple fade‑in/out and quick morphs; no complex camera moves to keep the scene stable for a short loop.
• Single Scene: All phases occur sequentially within one Manim Scene class.
• No extra text: Apart from the updated top title and bottom caption, all information is conveyed visually.