Question

Numbers less than 1000 where sum of the digits are divisible by 7 and the number is divisible by 3

Answer 1

The required
number is 993

Answer 2

Answer:

As per the divisibility test for 3 the sum of digits must be divisible by 3

and we are given that the sum of digits is divisible by 7 so we can conclude that the sum of digits must be divisible by L.C.M of 3 and 7 =21

now,

nos below 1000 which sum upto 21 are

399, 489, 498, 579, 588, 597, 669, 678, 687, 696, 759, 768 , 777, 786, 795,    

849, 858, 867, 876, 885, 894, 939, 948, 957, 966, 975, 984, 993.