By looking in a mirror, it appears that it is 6:30 in the clock. What is the real time?
(a) 5:30
When you look at a clock in a mirror, you see a reflection. A mirror causes lateral inversion, which means the image is flipped horizontally. The left side of the object appears on the right side in the mirror, and the right side appears on the left.
For a clock face, this means the numbers and hands appear reversed. For example, if the hour hand is pointing towards 3, in the mirror it will look like it's pointing towards 9. Similarly, if it's pointing towards 2, it will look like it's pointing towards 10.
A common and simple trick to find the real time when you know the mirror time (or vice versa) is to subtract the given time from 12:00. Since we work with hours and minutes, it's often easier to think of 12:00 as 11:60 (11 hours and 60 minutes).
The formula is:
\(\text{Real Time} = 12:00 - \text{Mirror Time}\)
or
\(\text{Real Time} = 11:60 - \text{Mirror Time}\)
The question states that the time seen in the mirror is 6:30.
We need to find the real time.
So, the real time is 5:30.
Let's check the options provided:
Based on our calculation and option verification, the real time is 5:30.
| Real Time | Calculation (11:60 - Real Time) | Mirror Time |
|---|---|---|
| 1:00 | 11:60 - 1:00 = 10:60 | 11:00 |
| 3:00 | 11:60 - 3:00 = 8:60 | 9:00 |
| 6:00 | 11:60 - 6:00 = 5:60 | 6:00 |
| 8:00 | 11:60 - 8:00 = 3:60 | 4:00 |
| 10:00 | 11:60 - 10:00 = 1:60 | 2:00 |
| 5:30 | 11:60 - 5:30 = 6:30 | 6:30 |
The method of subtracting from 12:00 (or 11:60) works because 12:00 acts as the line of reflection on a clock face. If you fold the clock face in half vertically along the 12 and 6, symmetric times add up to 12:00 (e.g., 1 and 11, 2 and 10, 3 and 9, etc.).
This method applies to both finding the real time from the mirror time and finding the mirror time from the real time.
For times involving seconds, you would subtract from 11:59:60.
Consider the hours 12 and 6. The number 12 remains visually similar in a mirror (though inverted), and 6 flips to look somewhat like a 9. The position of the hands at 12 and 6 are on the vertical axis, which is the line of symmetry for the reflection, so hands pointing exactly at 12 or 6 will still appear to point at 12 or 6, respectively.
For 6:30, the minute hand is pointing directly at 6. In the mirror, it will still appear to point at 6. The hour hand is halfway between 6 and 7. In the mirror, it will be halfway between 5 and 6, but on the opposite side of the 6. The hour hand will appear to be halfway between 5 and 6, pointing towards 5.
This visual analysis confirms the mathematical calculation: the time that appears as 6:30 in the mirror is actually 5:30.
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