Logical Reasoning
mediumQ. No. 19713
A clock shows 2:47. Calculate the acute or smaller reflex-complement angle made by its hands.
Last Updated:
A161.5°
B166.5°
C156.5°
D171.5°
Correct Answer: 161.5°Your Answer: A
Explanation
Correct answer: Option A — 161.5°. Their absolute difference is 198.5°; the smaller angle is 161.5°. Option B (166.5°) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option C (156.5°) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option D (171.5°) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error.
Important Notes
- Read the complete condition before calculating and write the required reference point, date, or clock time separately. This prevents a correct calculation from answering the reverse question.
- Keep units consistent. Reduce day differences modulo 7; treat 12 on a clock as zero for angle work; and convert gained or lost minutes into the same time unit as the stated interval.
- Check boundary cases explicitly: February, century years, noon, midnight, and an angle greater than 180 degrees often change the apparent answer. A century is a leap year only when divisible by 400.