A clock shows 3:15. What time will its mirror image show?

Explanation

For mirror-image clocks, the reflected time is obtained by subtracting the clock time from the reference value used for mirror clocks. Use 11:60 for times from 12:01 to 11:59; Physics Wallah gives the working rule for times between 1 and 11 o'clock. Subtracting 3:15 from 11:60 gives 60 - 15 = 45 minutes and 11 - 3 = 8 hours. So the mirror image reads 8:45, not a nearby-looking time such as 9:45 or 9:15.

Why the other options are wrong

• (B) 9:45 uses the correct reflected minutes, 45, but the hour is wrong because 11 - 3 gives 8, not 9.
• (C) 9:15 keeps 15 minutes and also gives the wrong hour, so it does not follow the 11:60 minus 3:15 mirror-clock rule.
• (D) 8:15 gets the reflected hour but leaves the minutes unchanged, whereas the mirror calculation changes 15 minutes to 45 minutes.

Concept

The clock mirror-image shortcut belongs to Reasoning and Mental Ability. RAS-style practice uses it to check whether candidates can apply a fixed rule quickly without being trapped by visually similar options.

Source

• Physics Wallah

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