hardmath

When is 1500 plus 20 and 1600 minus 40 the same thing?

In military time. Both refer to 3:20

Why this works

This riddle plays with the concept of military time, which uses a 24-hour clock format. In military time, 1500 hours is 3:00 PM, and when you add 20 minutes, you get 3:20 PM. Similarly, 1600 hours is 4:00 PM, and when you subtract 40 minutes, you also arrive at 3:20 PM. The clever twist lies in how the same time can be expressed through different arithmetic operations, leading to the same outcome in a unique context!

Common Wrong Answers

“In standard time”

In standard time, 1500 plus 20 would be 3:20 PM, but 1600 minus 40 would be 3:20 PM as well, making it seem correct but not addressing the unique aspect of military time.

“When adding hours and minutes”

Adding hours and minutes directly doesn't account for the military time format, which uses a 24-hour clock rather than a 12-hour clock.

“During a specific event”

The riddle is not context-specific to an event; it refers to a numerical relationship in timekeeping, which is not dependent on any particular event.

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