Question

A clock strikes once at 1 o’clock, twice at 2 o’clock, thrice at 3 o’clock and so on. How many times will it strike in 24 hours? A. 78
 B. 136
 C. 156
 D. 196

Answer 1

B).................
....................
..

Answer 2

c)156
in one day ie 24 hours every time appears 2 times hence
$2(1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12) = 156$