Clock Time Puzzle is a five-card educational game rendered on a Canvas. Each card displays a target time, and the player adjusts a selected digital time until both the readout and the analog hands match. The selected time and Canvas clock update together, so the display provides a direct visual check of the calculation.
The game has a fixed route rather than a timer or changing set of targets. Once every card has been solved correctly, the player receives 1,000 points. Clock Time Puzzle is educational entertainment, not a standardized teaching assessment or a guarantee that a player has mastered timekeeping.
The Fixed Route and Exact Score
The five targets must be solved in this order: 3:00, 6:30, 9:45, 12:00, and 2:25. Each exact submission awards 200 points. There is no additional multiplier or bonus step: five correct cards at 200 points each produce exactly 1,000 points.
The route mixes two exact hour-mark positions with three continuous positions. At 3:00 and 12:00, the hour hand sits directly on an hour mark. At 6:30, 9:45, and 2:25, it has moved partway toward the next number. That mixture makes the fixed sequence useful for checking both the basic geometry and the continuous hour-hand formula.
A new or restarted run starts on the first card at 12:00. The current target, selected time, current angles, formula, status, mistake count, feedback, and score remain visible while a card is active.
Controls, Valid Times, and Atomic Rejections
The hour control accepts values from 1 through 12. It steps through those twelve values in order and wraps from 12 back to 1. The minute control accepts 00, 05, 10, 15, 20, 25, 30, 35, 40, 45, 50, and 55. Left and Right changes wrap in the same five-minute pattern.
Pointer and touch-screen players use the on-screen buttons. Keyboard players can use Up and Down to change the hour by one, Left and Right to change the minute by five, and Enter to submit. Pressing R restarts the game when focus is outside an editing control. Restart returns to 12:00 on the first card and resets the current score and error count to zero.
Invalid product inputs are atomic no-ops. A control action does not partially change the time when the requested value is outside the supported range, noninteger, or off-step. For example, hour 15, minute 02, minute 60, or a noninteger minute is ignored as an invalid action. Valid product minutes must always be one of the twelve five-minute positions from 00 through 55.
The game’s playable controls use a 12-hour range. A separate lower-level angle function accepts conventional evidence values from 0 through 23 hours and 0 through 59 minutes, which explains why vectors such as 20:14 can appear in mathematical checks without becoming selectable game times.
Completion and deadlock are terminal states. After all five cards are complete, or after a second distinct wrong setting closes the clock file, time adjustment and submission are frozen until the game is restarted.
How the Continuous Hand Angles Work
The minute hand is the simpler calculation. It completes a 360-degree rotation in 60 minutes, so it travels six degrees for every minute:
minuteAngle = 6 × minute
The hour hand completes the same 360-degree rotation in 12 hours. It therefore moves 30 degrees per hour and half a degree per elapsed minute:
hourAngle = 30 × (hour mod 12) + 0.5 × minute
The modulo operation maps 12 to 0 because a 12-hour face repeats after a complete revolution. Thus, 12:00 produces an hour angle of 0 degrees, while 3:00 produces 90 degrees. The game does not accept hour 15 as a product control, but the mathematical term is what prevents the formula from exceeding the familiar 12-hour face.
Consider 6:30. The minute angle is 6 × 30 = 180 degrees, placing the minute hand at 6. The hour angle is 30 × 6 + 0.5 × 30 = 195 degrees. The hour hand is therefore halfway between 6 and 7 rather than directly on either number.
The same continuous calculation is more demanding at 9:45. The minute angle is 270 degrees, while the hour angle is 30 × 9 + 0.5 × 45 = 292.5 degrees. After 45 minutes, the hour hand has traveled three-quarters of the way from 9 toward 10. Treating it as fixed at 270 degrees would miss the extra 22.5 degrees contributed by the elapsed minutes.
The University of Cambridge NRICH explanation of clock-face angles uses 20:14 as a worked example and supports the same hand-rate relationships. The Rutgers University explanation of advanced clock topics independently confirms the continuous hour-hand movement and the minute hand’s six-degree relationship. These sources support the geometry; they do not validate the game’s score, controls, or target order.
What the Canvas and Angle Readout Show
The Canvas contains no animation loop. It does not tick on its own or interpolate smoothly between frames. Instead, it redraws from the currently selected hour and minute whenever those values change. The digital selection and both Canvas hands update together.
The visible status is therefore a useful cross-check. If the current card targets 9:45 and the player selects 8:15, the minute angle is 90 degrees and the hour angle is 247.5 degrees. The display can be read in minute-angle/hour-angle order, making it clear that the current clock does not yet match the target’s 270/292.5-degree pair.
Step-by-Step Walkthrough of All Five Cards
- Read card one, which targets 3:00. Adjust the selected time to 3:00 using the hour and minute controls. The expected minute/hour pair is 0/90 degrees. Submit with Enter or the on-screen submit control for 200 points.
- Continue to card two and select 6:30. The minute angle is 180 degrees, and the continuous hour angle is 195 degrees. The hour hand should appear halfway between 6 and 7. Submit the exact target for 200 points.
- On card three, set 9:45. The minute hand moves to 270 degrees, while the hour hand moves to 292.5 degrees. That is 270 degrees at 9 plus another 22.5 degrees from the 45 elapsed minutes. Submit the exact selection.
- Card four returns to an exact hour position: 12:00. Both calculated angles are 0 degrees, so the hands stack at the top of the Canvas clock. Submit 12:00 for another 200 points.
- Set the final target to 2:25. Its minute angle is 150 degrees, and its hour angle is 72.5 degrees. The hour hand has moved 12.5 degrees past 2. Submit the exact target to complete the route.
After the fifth exact submission, the score reaches exactly 1,000 and the completed game becomes terminal. Further time adjustments and submissions are frozen until the player restarts.
Nine Literal Time-and-Angle Vectors
The game’s independent checks hold literal expected values rather than deriving all expected angles from the production implementation. The following release vectors cover the five fixed route targets plus four additional mathematical or evidence references. The angle pairs are written as minute angle/hour angle, measured clockwise from 12.
| Time Vector | Minute Angle | Hour Angle | Route or Evidence Role |
|---|---|---|---|
| 12:00 | 0° | 0° | Card 4 and the restart value. |
| 3:00 | 0° | 90° | Card 1. |
| 6:30 | 180° | 195° | Card 2; hour hand is halfway to 7. |
| 9:45 | 270° | 292.5° | Card 3; hour hand is three-quarters of the way to 10. |
| 12:30 | 180° | 15° | Release vector, not an extra game card. |
| 3:15 | 90° | 97.5° | Release vector, not an extra game card. |
| 8:24 | 144° | 252° | Release vector, not an extra game card. |
| 20:14 | 84° | 247° | Lower-level evidence vector only. |
| 2:25 | 150° | 72.5° | Card 5; hour hand is 12.5 degrees past 2. |
The five route targets account for the playable 1,000-point run. The other listed times provide literal angle references and test coverage; they do not add hidden cards, alternate scoring rules, or selectable 24-hour inputs.
Wrong Submissions, Recovery, and Deadlock
A wrong submission creates one recoverable error identified by the current round and the selected hour and minute. Submitting that identical wrong setting again is a no-op, so the duplicate action does not create another error or advance the card.
The recovery window ends when the player submits a second, distinct wrong setting. That action closes the current clock file and creates a deadlock state. Time adjustment and submission then remain frozen. This is different from repeating the same mistake, which leaves the same recoverable error in place.
The status, target time, selected time, formula, current angles, mistakes, and feedback remain visible throughout. Players can use that information to correct the first distinct error before changing to another incorrect hour-and-minute combination. When focus is outside an editing control, R provides a full restart to 12:00 on card one, zero current points, and zero errors.
What the Game Does—and What the Math Sources Do Not—Establish
All processing stays in the browser. The game requires no account, upload, API, alarm, scheduling service, or timer dependency, and it makes no timezone claim. No personal clock history is stored or transmitted. The shared game shell supplies a best score, while the current route and current point total remain visible during play.
The two cited sources establish the minute- and hour-hand rates used in the formulas. They do not confirm that the game accepts those values, that the five cards appear in the stated order, or that correct submissions receive 200 points each. Those gameplay details come from the product itself. The game should therefore be treated as a transparent practice puzzle rather than as a validated assessment of timekeeping skill.
For a different browser-based puzzle format, this logic grid puzzle walkthrough covers a separate genre.