Saved Bookmarks
| 1. |
Find which of the following numbers are divisible by 11 :(i) 5918(ii) 68,717(iii) 3882(iv) 10857 |
|
Answer» A number is divisible by 11, if the difference of sumof its digits in odd places from the right side and the sum of its digits in even places from the right side is divisible by 11. (i) 5918 Sum of digits at odd places = 5 + 1=6 and, sum of digits at even places = 9 + 8= 17 Their difference = 17 – 6 = 11 Which is divisible by 11 5918 is divisible by 11. (ii) 68, 717 Sum of digits at odd places = 6 + 7 + 7 = 20 and, sum of digits at even places = 8 + 1 =9 Difference = 20 – 9 = 11 which is divisible by 11 68717, is divisible by 11. (iii) 3882 Sum of digits at odd places = 3 + 8 = 11 and, Sum of digits at even places = 8 + 2 = 10 Difference = 11 – 10 = 1 Which is not divisible by 11 3882 is not divisible by 11. (iv) 10857 Sum of digits at odd places =1 + 8 + 7 = 16 and, Sum of digits at even places = 0 + 5 = 5 Difference = 16 – 5 = 11 which is divisible by 11 10857 is divisible by 11. |
|