Saved Bookmarks
| 1. |
1. A watch. At the hour. The bell rings twice, the bell rings 2 times at 2 o'clock, •••, the bell rings 12 times at 12 o'clock. How many times will Mate ring the bell in 24 hours? . A 78 B) 136 C) 156 D 196 |
|
Answer» ell rings in 12 hours = 1+2+...+12Total bell rings in 24 hours = 2(1+2+...+12) {because, after 12 o'clock, the clock resets and STARTS from 1 instead of 13}TOTAL bell rings = 2(78)= 156 |
|