When asked about the time, Amit replied: "If you add one quarter of the time…

2024

When asked about the time, Amit replied: "If you add one quarter of the time from midnight till now to half the time from now till the next midnight, you get the time." What is the time now?

  1. A.

    48/5 hours

  2. B.

    48/7 hours

  3. C.

    51/6 hours

  4. D.

    85/4 hours

Attempted by 1 students.

Show answer & explanation

Correct answer: A

A statement relating "time elapsed since midnight" and "time remaining till the next midnight" to the current time is a linear-equation problem: if the current time is x hours after midnight (0 ≤ x < 24), the elapsed time equals x and the remaining time to the next midnight equals (24 − x). Any fractional combination of these two spans that is said to equal the current time becomes one linear equation in x.

  1. Let the current time be x hours past midnight. Elapsed time since midnight = x; remaining time to the next midnight = 24 − x.

  2. Amit's statement translates to: one quarter of the elapsed time plus half the remaining time equals the current time — (1/4)x + (1/2)(24 − x) = x.

  3. Expand the bracket: (1/4)x + 12 − (1/2)x = x.

  4. Combine the x-terms on the left: 12 − (1/4)x = x.

  5. Move the x-term to the right and combine: 12 = x + (1/4)x = (5/4)x.

  6. Solve for x: x = 12 × 4/5 = 48/5.

Check: with x = 48/5, elapsed time = 48/5 and remaining time = 24 − 48/5 = 72/5. One quarter of the elapsed time is 12/5 and half the remaining time is 36/5; their sum, 12/5 + 36/5 = 48/5, equals x, confirming the value.

So the current time is 48/5 hours past midnight (9.6 hours, i.e. 9:36).

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