A clock struck 1 time on 1 O'clock, 2 times on 2 O'clock, 3 times on 3 O'clock and so on. How many times the clock struck in twelve hours?
- 75 Times
- 77 Times
- 78 Times
- 79 Times
Correct answer: C
A clock strikes 1+2+⋯+12 = 12×13÷2 = 78 times in twelve hours.
Appeared in 1 past paper
Category: Arithmetic and Analytical Reasoning