How many times do the hands of a clock coincide in 24 hours?
A20
B22
C24
D44
✓ Correct Answer: B (22)
Explanation: Hands coincide 11 times in every 12 hours (not 12 — as 12:00 is shared at both ends). In 24 hours: 11 × 2 = 22 times.
Question 15Clock
The minute hand gains how many degrees over the hour hand in one minute?
A5°
B5.5°
C6°
D6.5°
✓ Correct Answer: B (5.5°)
Explanation: Minute hand moves 6°/min; hour hand moves 0.5°/min. Relative gain = 6 − 0.5 = 5.5° per minute. This is the basis of the angle formula |30H − 5.5M|.
Calendar
Question 16Calendar
Which of the following is NOT a leap year?
A2000
B1900
C2024
D1600
✓ Correct Answer: B (1900)
Explanation: A century year is a leap year only if divisible by 400. 1900 is not divisible by 400 → NOT a leap year. 2000 and 1600 are divisible by 400 and are leap years.
Question 17Calendar
If 1st January 2024 is a Monday, what day of the week is 1st January 2025?
AMonday
BTuesday
CWednesday
DThursday
✓ Correct Answer: C (Wednesday)
Explanation: 2024 is a leap year → 366 days = 52 weeks + 2 odd days. Monday + 2 = Wednesday.
Question 18Calendar
A non-leap year has how many odd days?
A0
B1
C2
D3
✓ Correct Answer: B (1)
Explanation: A non-leap year has 365 days = 52 weeks + 1 odd day. A leap year has 366 days = 52 weeks + 2 odd days.
Time, Work & Distance
Question 19Time & Work
A can do a piece of work in 12 days and B in 18 days. Together they finish it in:
A6 days
B7.2 days
C8 days
D9 days
✓ Correct Answer: B (7.2 days)
Explanation: Combined rate = 1/12 + 1/18 = 3/36 + 2/36 = 5/36 → Time = 36/5 = 7.2 days
Question 20Pipes & Cisterns
A pipe fills a tank in 4 hours; another empties it in 12 hours. When both are open together, the tank fills in:
A4 hours
B6 hours
C8 hours
D12 hours
✓ Correct Answer: B (6 hours)
Explanation: Net rate = 1/4 − 1/12 = 3/12 − 1/12 = 2/12 = 1/6 → Time = 6 hours
Question 21Speed & Distance
A train 150 m long passes a pole in 15 seconds. Its speed in km/h is:
A30 km/h
B36 km/h
C40 km/h
D54 km/h
✓ Correct Answer: B (36 km/h)
Explanation: Speed = 150/15 = 10 m/s → 10 × (18/5) = 36 km/h
Question 22Speed & Distance
Two persons walk towards each other from points 18 km apart at 4 km/h and 5 km/h respectively. After how many hours do they meet?
A1 hour
B1.5 hours
C2 hours
D2.5 hours
✓ Correct Answer: C (2 hours)
Explanation: Relative speed = 4 + 5 = 9 km/h → Time = 18 / 9 = 2 hours
Seating Arrangements
Question 23Seating Arrangement
In a row of 20 students, Ravi is 8th from the left. His position from the right is:
A11th
B12th
C13th
D14th
✓ Correct Answer: C (13th)
Explanation: Position from right = (Total + 1) − Position from left = 21 − 8 = 13th
Question 24Seating Arrangement
P is 7th from the left in a row. Q is 9th from the right. They exchange positions; now P is 11th from the left. How many students are in the row?
A17
B18
C19
D20
✓ Correct Answer: C (19)
Explanation: After exchange, P occupies Q's original position (9th from right) and is 11th from left. Total = (11 + 9) − 1 = 19 students
Question 25Seating Arrangement
In a class, Amit is ranked 8th from the top and 32nd from the bottom. How many students are in the class?
A37
B38
C39
D40
✓ Correct Answer: C (39)
Explanation: Total = (Rank from top + Rank from bottom) − 1 = (8 + 32) − 1 = 39 students
Question 26Seating Arrangement
5 people A, B, C, D, E sit in a row. A is to the immediate left of B, and C is to the immediate right of B. D is to the immediate left of A. Who is in the middle?
AA
BB
CC
DD
✓ Correct Answer: B (B)
Explanation: D is left of A; A is left of B; B is left of C; E must be rightmost. Order: D — A — B — C — E → B is in the middle (3rd position).
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Final Answer: The leak alone empties the full tank in 24 hours
Question 16Speed & Distance
Two trains start simultaneously from stations A and B which are 250 km apart, moving towards each other at 60 km/h and 40 km/h. After how many hours do they meet, and how far from A?
Solution:
Relative speed = 60 + 40 = 100 km/h
Time to meet = 250 ÷ 100 = 2.5 hours
Distance covered by train from A = 60 × 2.5 = 150 km from A
Final Answer: They meet after 2.5 hours, at 150 km from A
Seating Arrangements
Question 17Seating Arrangement
In a class of 35 students, Meena ranks 10th from the top. Priya is 5 ranks below Meena. What is Priya's rank from the bottom?
Solution:
Priya's rank from top = 10 + 5 = 15th
Priya's rank from bottom = (Total + 1) − Rank from top = 36 − 15 = 21st
Final Answer: Priya's rank from the bottom is 21st
Question 18Seating Arrangement
In a row, Anil is 12th from the left and 8th from the right. Suresh is 3 places to the right of Anil. How many people are in the row, and what is Suresh's position from the right?
Solution:
Total = (12 + 8) − 1 = 19 people
Suresh's position from left = 12 + 3 = 15th
Suresh's position from right = (19 + 1) − 15 = 5th
Total = 19 people | Suresh is 5th from the right
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A computer science teacher explains that computers store all data in binary (base 2) using only 0s and 1s. She tells the class: "The number of unique values storable in n bits is 2n. Conversely, the number of bits required = log2(total values)."
She gives the class a set of tasks using the ASCII code for the letter 'A', which equals 65 in decimal.
Question 1:
Convert the ASCII code of 'A' (decimal 65) into binary. Show all steps.