The digit 1 is attached to the right of a 3-digit number making it a 4-digit number which is 7777 more than the given number. The sum of the digits of the number is (A)23 (B)18 (C)17 (D)16 (E)21 The OA is B.

harsh.champ wrote:The digit 1 is attached to the right of a 3-digit number making it a 4-digit number which is 7777 more than the given number. The sum of the digits of the number is (A)23 (B)18 (C)17 (D)16 (E)21 The OA is B. Let the 3-digits of the given number be a, b and c, so that abc1 may be the 4 digit number. The difference between the numbers is (1000a + 100b + 10c + 1) – (100a + 10b + c) = 7777 --> 9 (100a + 10b + c) = 7776 --> 100a + 10b + c = 864 (which is the given number) So, the sum of the digits of the given number is 18.[spoiler]The answer is option (B)[/spoiler]

harsh.champ wrote:The digit 1 is attached to the right of a 3-digit number making it a 4-digit number which is 7777 more than the given number. The sum of the digits of the number is (A)23 (B)18 (C)17 (D)16 (E)21 The OA is B. say abc be the number 100a + 10b +c +7777 = 1000a + 100b + 10c + a 7777 = 900a + 90 b +9 c +1 = 9 (100a+10b+c) =1 (100a+10b+c) = 7776/9 =864 sum of digits = 16

ajith wrote:harsh.champ wrote:The digit 1 is attached to the right of a 3-digit number making it a 4-digit number which is 7777 more than the given number. The sum of the digits of the number is (A)23 (B)18 (C)17 (D)16 (E)21 The OA is B. say abc be the number 100a + 10b +c +7777 = 1000a + 100b + 10c + a 7777 = 900a + 90 b +9 c +1 = 9 (100a+10b+c) =1 (100a+10b+c) = 7776/9 =864 sum of digits = 16 ajit you did a calculation mistake sum of digits of 864 = 8+6+4 =18

- - - 1 (-)x ........ 7 7 7 7 1-x i.e, 11-x = 7. So, x=4 - - 4 1 (-)y 4 ........ 7 7 7 7 4-y i.e, 13-y=7. So, y=6 - 6 4 1 (-)z 6 4 ....... 7 7 7 7 6-z i.e, 15-z=7.So, z=8 8 6 4 1 (-)8 6 4 ....... 7 7 7 7 ....... Sum of the digits of the number is 8+6+4 =18 .